[PATCH v1 1/7] iio: accel: st_accel: Move platform data from header to C file

[PATCH v1 1/7] iio: accel: st_accel: Move platform data from header to C file

[Andy Shevchenko]

Platform data is solely used by one file. Don't share it with others.

While at it, drop unneeded anymore __maybe_unused and fix kernel doc
to avoid warning:

  st_accel_core.c:1079: error: Cannot parse struct or union!

by converting to a simple comment. It is described at the declaration.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/iio/accel/st_accel.h      | 8 --------
 drivers/iio/accel/st_accel_core.c | 5 +++++
 2 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/drivers/iio/accel/st_accel.h b/drivers/iio/accel/st_accel.h
index 5d356288e001..181ebe79c4eb 100644
--- a/drivers/iio/accel/st_accel.h
+++ b/drivers/iio/accel/st_accel.h
@@ -62,14 +62,6 @@ enum st_accel_type {
 #define LIS2DE12_ACCEL_DEV_NAME		"lis2de12"
 #define LIS2HH12_ACCEL_DEV_NAME		"lis2hh12"
 
-/**
-* struct st_sensors_platform_data - default accel platform data
-* @drdy_int_pin: default accel DRDY is available on INT1 pin.
-*/
-static __maybe_unused const struct st_sensors_platform_data default_accel_pdata = {
-	.drdy_int_pin = 1,
-};
-
 const struct st_sensor_settings *st_accel_get_settings(const char *name);
 int st_accel_common_probe(struct iio_dev *indio_dev);
 void st_accel_common_remove(struct iio_dev *indio_dev);
diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c
index 43c50167d220..a1bd7e3b912e 100644
--- a/drivers/iio/accel/st_accel_core.c
+++ b/drivers/iio/accel/st_accel_core.c
@@ -983,6 +983,11 @@ static const struct st_sensor_settings st_accel_sensors_settings[] = {
 
 };
 
+/* Default accel DRDY is available on INT1 pin */
+static const struct st_sensors_platform_data default_accel_pdata = {
+	.drdy_int_pin = 1,
+};
+
 static int st_accel_read_raw(struct iio_dev *indio_dev,
 			struct iio_chan_spec const *ch, int *val,
 							int *val2, long mask)
-- 
2.30.2

[PATCH v1 2/7] iio: gyro: st_gyro: Move platform data from header to C file

[Andy Shevchenko]

Platform data is solely used by one file. Don't share it with others.

While at it, drop unneeded anymore __maybe_unused and fix kernel doc
to avoid warning:

  st_gyro_core.c:366: error: Cannot parse struct or union!

by converting to a simple comment. It is described at the declaration.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/iio/gyro/st_gyro.h      | 8 --------
 drivers/iio/gyro/st_gyro_core.c | 5 +++++
 2 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/drivers/iio/gyro/st_gyro.h b/drivers/iio/gyro/st_gyro.h
index fd9171cc3aba..b385fe664dcc 100644
--- a/drivers/iio/gyro/st_gyro.h
+++ b/drivers/iio/gyro/st_gyro.h
@@ -24,14 +24,6 @@
 #define LSM330_GYRO_DEV_NAME		"lsm330_gyro"
 #define LSM9DS0_GYRO_DEV_NAME		"lsm9ds0_gyro"
 
-/**
- * struct st_sensors_platform_data - gyro platform data
- * @drdy_int_pin: DRDY on gyros is available only on INT2 pin.
- */
-static __maybe_unused const struct st_sensors_platform_data gyro_pdata = {
-	.drdy_int_pin = 2,
-};
-
 const struct st_sensor_settings *st_gyro_get_settings(const char *name);
 int st_gyro_common_probe(struct iio_dev *indio_dev);
 void st_gyro_common_remove(struct iio_dev *indio_dev);
diff --git a/drivers/iio/gyro/st_gyro_core.c b/drivers/iio/gyro/st_gyro_core.c
index c8aa051995d3..e000504e1df4 100644
--- a/drivers/iio/gyro/st_gyro_core.c
+++ b/drivers/iio/gyro/st_gyro_core.c
@@ -357,6 +357,11 @@ static const struct st_sensor_settings st_gyro_sensors_settings[] = {
 	},
 };
 
+/* DRDY on gyros is available only on INT2 pin */
+static const struct st_sensors_platform_data gyro_pdata = {
+	.drdy_int_pin = 2,
+};
+
 static int st_gyro_read_raw(struct iio_dev *indio_dev,
 			struct iio_chan_spec const *ch, int *val,
 							int *val2, long mask)
-- 
2.30.2

[PATCH v1 3/7] iio: magnetometer: st_magn: Provide default platform data

[Andy Shevchenko]

Provide default platform data for magnetometer in case it supports DRDY.

One case is LSM9DS0 IMU, on which it is the case. Since accelerometer
is using INT1, default magnetometer to INT2.

While at it, update description of the drdy_int_pin field.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/iio/magnetometer/st_magn_core.c        | 11 ++++++++++-
 include/linux/platform_data/st_sensors_pdata.h |  3 ++-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/magnetometer/st_magn_core.c b/drivers/iio/magnetometer/st_magn_core.c
index 79de721e6015..cf3722e42419 100644
--- a/drivers/iio/magnetometer/st_magn_core.c
+++ b/drivers/iio/magnetometer/st_magn_core.c
@@ -382,6 +382,11 @@ static const struct st_sensor_settings st_magn_sensors_settings[] = {
 	},
 };
 
+/* Default magn DRDY is available on INT2 pin */
+static const struct st_sensors_platform_data default_magn_pdata = {
+	.drdy_int_pin = 2,
+};
+
 static int st_magn_read_raw(struct iio_dev *indio_dev,
 			struct iio_chan_spec const *ch, int *val,
 							int *val2, long mask)
@@ -489,6 +494,7 @@ EXPORT_SYMBOL(st_magn_get_settings);
 int st_magn_common_probe(struct iio_dev *indio_dev)
 {
 	struct st_sensor_data *mdata = iio_priv(indio_dev);
+	struct st_sensors_platform_data *pdata = dev_get_platdata(mdata->dev);
 	int err;
 
 	indio_dev->modes = INDIO_DIRECT_MODE;
@@ -509,7 +515,10 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
 	mdata->current_fullscale = &mdata->sensor_settings->fs.fs_avl[0];
 	mdata->odr = mdata->sensor_settings->odr.odr_avl[0].hz;
 
-	err = st_sensors_init_sensor(indio_dev, NULL);
+	if (!pdata)
+		pdata = (struct st_sensors_platform_data *)&default_magn_pdata;
+
+	err = st_sensors_init_sensor(indio_dev, pdata);
 	if (err < 0)
 		goto st_magn_power_off;
 
diff --git a/include/linux/platform_data/st_sensors_pdata.h b/include/linux/platform_data/st_sensors_pdata.h
index e40b28ca892e..897051e51b78 100644
--- a/include/linux/platform_data/st_sensors_pdata.h
+++ b/include/linux/platform_data/st_sensors_pdata.h
@@ -13,8 +13,9 @@
 /**
  * struct st_sensors_platform_data - Platform data for the ST sensors
  * @drdy_int_pin: Redirect DRDY on pin 1 (1) or pin 2 (2).
- *	Available only for accelerometer and pressure sensors.
+ *	Available only for accelerometer, magnetometer and pressure sensors.
  *	Accelerometer DRDY on LSM330 available only on pin 1 (see datasheet).
+ *	Magnetometer DRDY is supported only on LSM9DS0.
  * @open_drain: set the interrupt line to be open drain if possible.
  * @spi_3wire: enable spi-3wire mode.
  * @pullups: enable/disable i2c controller pullup resistors.
-- 
2.30.2

[PATCH v1 4/7] iio: st_sensors: Call st_sensors_power_enable() from bus drivers

[Andy Shevchenko]

In case we would initialize two IIO devices from one physical device,
we shouldn't have a clash on regulators. That's why move
st_sensors_power_enable() call from core to bus drivers.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/iio/accel/st_accel_core.c       | 21 +++++----------------
 drivers/iio/accel/st_accel_i2c.c        | 17 +++++++++++++++--
 drivers/iio/accel/st_accel_spi.c        | 17 +++++++++++++++--
 drivers/iio/gyro/st_gyro_core.c         | 15 +++------------
 drivers/iio/gyro/st_gyro_i2c.c          | 17 +++++++++++++++--
 drivers/iio/gyro/st_gyro_spi.c          | 17 +++++++++++++++--
 drivers/iio/magnetometer/st_magn_core.c | 15 +++------------
 drivers/iio/magnetometer/st_magn_i2c.c  | 14 +++++++++++++-
 drivers/iio/magnetometer/st_magn_spi.c  | 14 +++++++++++++-
 drivers/iio/pressure/st_pressure_core.c | 15 +++------------
 drivers/iio/pressure/st_pressure_i2c.c  | 17 +++++++++++++++--
 drivers/iio/pressure/st_pressure_spi.c  | 17 +++++++++++++++--
 12 files changed, 130 insertions(+), 66 deletions(-)

diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c
index a1bd7e3b912e..5c258c1ca62d 100644
--- a/drivers/iio/accel/st_accel_core.c
+++ b/drivers/iio/accel/st_accel_core.c
@@ -1260,13 +1260,9 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &accel_info;
 
-	err = st_sensors_power_enable(indio_dev);
-	if (err)
-		return err;
-
 	err = st_sensors_verify_id(indio_dev);
 	if (err < 0)
-		goto st_accel_power_off;
+		return err;
 
 	adata->num_data_channels = ST_ACCEL_NUMBER_DATA_CHANNELS;
 	indio_dev->num_channels = ST_SENSORS_NUMBER_ALL_CHANNELS;
@@ -1275,10 +1271,8 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
 	channels = devm_kmemdup(&indio_dev->dev,
 				adata->sensor_settings->ch,
 				channels_size, GFP_KERNEL);
-	if (!channels) {
-		err = -ENOMEM;
-		goto st_accel_power_off;
-	}
+	if (!channels)
+		return -ENOMEM;
 
 	if (apply_acpi_orientation(indio_dev, channels))
 		dev_warn(&indio_dev->dev,
@@ -1293,11 +1287,11 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
 
 	err = st_sensors_init_sensor(indio_dev, pdata);
 	if (err < 0)
-		goto st_accel_power_off;
+		return err;
 
 	err = st_accel_allocate_ring(indio_dev);
 	if (err < 0)
-		goto st_accel_power_off;
+		return err;
 
 	if (adata->irq > 0) {
 		err = st_sensors_allocate_trigger(indio_dev,
@@ -1320,9 +1314,6 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
 		st_sensors_deallocate_trigger(indio_dev);
 st_accel_probe_trigger_error:
 	st_accel_deallocate_ring(indio_dev);
-st_accel_power_off:
-	st_sensors_power_disable(indio_dev);
-
 	return err;
 }
 EXPORT_SYMBOL(st_accel_common_probe);
@@ -1331,8 +1322,6 @@ void st_accel_common_remove(struct iio_dev *indio_dev)
 {
 	struct st_sensor_data *adata = iio_priv(indio_dev);
 
-	st_sensors_power_disable(indio_dev);
-
 	iio_device_unregister(indio_dev);
 	if (adata->irq > 0)
 		st_sensors_deallocate_trigger(indio_dev);
diff --git a/drivers/iio/accel/st_accel_i2c.c b/drivers/iio/accel/st_accel_i2c.c
index 360e16f2cadb..95e305b88d5e 100644
--- a/drivers/iio/accel/st_accel_i2c.c
+++ b/drivers/iio/accel/st_accel_i2c.c
@@ -174,16 +174,29 @@ static int st_accel_i2c_probe(struct i2c_client *client)
 	if (ret < 0)
 		return ret;
 
+	ret = st_sensors_power_enable(indio_dev);
+	if (ret)
+		return ret;
+
 	ret = st_accel_common_probe(indio_dev);
 	if (ret < 0)
-		return ret;
+		goto st_accel_power_off;
 
 	return 0;
+
+st_accel_power_off:
+	st_sensors_power_disable(indio_dev);
+
+	return ret;
 }
 
 static int st_accel_i2c_remove(struct i2c_client *client)
 {
-	st_accel_common_remove(i2c_get_clientdata(client));
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	st_sensors_power_disable(indio_dev);
+
+	st_accel_common_remove(indio_dev);
 
 	return 0;
 }
diff --git a/drivers/iio/accel/st_accel_spi.c b/drivers/iio/accel/st_accel_spi.c
index 568ff1bae0ee..83d3308ce5cc 100644
--- a/drivers/iio/accel/st_accel_spi.c
+++ b/drivers/iio/accel/st_accel_spi.c
@@ -123,16 +123,29 @@ static int st_accel_spi_probe(struct spi_device *spi)
 	if (err < 0)
 		return err;
 
+	err = st_sensors_power_enable(indio_dev);
+	if (err)
+		return err;
+
 	err = st_accel_common_probe(indio_dev);
 	if (err < 0)
-		return err;
+		goto st_accel_power_off;
 
 	return 0;
+
+st_accel_power_off:
+	st_sensors_power_disable(indio_dev);
+
+	return err;
 }
 
 static int st_accel_spi_remove(struct spi_device *spi)
 {
-	st_accel_common_remove(spi_get_drvdata(spi));
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+
+	st_sensors_power_disable(indio_dev);
+
+	st_accel_common_remove(indio_dev);
 
 	return 0;
 }
diff --git a/drivers/iio/gyro/st_gyro_core.c b/drivers/iio/gyro/st_gyro_core.c
index e000504e1df4..ee3f0ea96ac5 100644
--- a/drivers/iio/gyro/st_gyro_core.c
+++ b/drivers/iio/gyro/st_gyro_core.c
@@ -471,13 +471,9 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &gyro_info;
 
-	err = st_sensors_power_enable(indio_dev);
-	if (err)
-		return err;
-
 	err = st_sensors_verify_id(indio_dev);
 	if (err < 0)
-		goto st_gyro_power_off;
+		return err;
 
 	gdata->num_data_channels = ST_GYRO_NUMBER_DATA_CHANNELS;
 	indio_dev->channels = gdata->sensor_settings->ch;
@@ -490,11 +486,11 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
 
 	err = st_sensors_init_sensor(indio_dev, pdata);
 	if (err < 0)
-		goto st_gyro_power_off;
+		return err;
 
 	err = st_gyro_allocate_ring(indio_dev);
 	if (err < 0)
-		goto st_gyro_power_off;
+		return err;
 
 	if (gdata->irq > 0) {
 		err = st_sensors_allocate_trigger(indio_dev,
@@ -517,9 +513,6 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
 		st_sensors_deallocate_trigger(indio_dev);
 st_gyro_probe_trigger_error:
 	st_gyro_deallocate_ring(indio_dev);
-st_gyro_power_off:
-	st_sensors_power_disable(indio_dev);
-
 	return err;
 }
 EXPORT_SYMBOL(st_gyro_common_probe);
@@ -528,8 +521,6 @@ void st_gyro_common_remove(struct iio_dev *indio_dev)
 {
 	struct st_sensor_data *gdata = iio_priv(indio_dev);
 
-	st_sensors_power_disable(indio_dev);
-
 	iio_device_unregister(indio_dev);
 	if (gdata->irq > 0)
 		st_sensors_deallocate_trigger(indio_dev);
diff --git a/drivers/iio/gyro/st_gyro_i2c.c b/drivers/iio/gyro/st_gyro_i2c.c
index 8190966e6ff0..a25cc0379e16 100644
--- a/drivers/iio/gyro/st_gyro_i2c.c
+++ b/drivers/iio/gyro/st_gyro_i2c.c
@@ -86,16 +86,29 @@ static int st_gyro_i2c_probe(struct i2c_client *client,
 	if (err < 0)
 		return err;
 
+	err = st_sensors_power_enable(indio_dev);
+	if (err)
+		return err;
+
 	err = st_gyro_common_probe(indio_dev);
 	if (err < 0)
-		return err;
+		goto st_gyro_power_off;
 
 	return 0;
+
+st_gyro_power_off:
+	st_sensors_power_disable(indio_dev);
+
+	return err;
 }
 
 static int st_gyro_i2c_remove(struct i2c_client *client)
 {
-	st_gyro_common_remove(i2c_get_clientdata(client));
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	st_sensors_power_disable(indio_dev);
+
+	st_gyro_common_remove(indio_dev);
 
 	return 0;
 }
diff --git a/drivers/iio/gyro/st_gyro_spi.c b/drivers/iio/gyro/st_gyro_spi.c
index efb862763ca3..18d6a2aeda45 100644
--- a/drivers/iio/gyro/st_gyro_spi.c
+++ b/drivers/iio/gyro/st_gyro_spi.c
@@ -90,16 +90,29 @@ static int st_gyro_spi_probe(struct spi_device *spi)
 	if (err < 0)
 		return err;
 
+	err = st_sensors_power_enable(indio_dev);
+	if (err)
+		return err;
+
 	err = st_gyro_common_probe(indio_dev);
 	if (err < 0)
-		return err;
+		goto st_gyro_power_off;
 
 	return 0;
+
+st_gyro_power_off:
+	st_sensors_power_disable(indio_dev);
+
+	return err;
 }
 
 static int st_gyro_spi_remove(struct spi_device *spi)
 {
-	st_gyro_common_remove(spi_get_drvdata(spi));
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+
+	st_sensors_power_disable(indio_dev);
+
+	st_gyro_common_remove(indio_dev);
 
 	return 0;
 }
diff --git a/drivers/iio/magnetometer/st_magn_core.c b/drivers/iio/magnetometer/st_magn_core.c
index cf3722e42419..018b2523edfe 100644
--- a/drivers/iio/magnetometer/st_magn_core.c
+++ b/drivers/iio/magnetometer/st_magn_core.c
@@ -500,13 +500,9 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &magn_info;
 
-	err = st_sensors_power_enable(indio_dev);
-	if (err)
-		return err;
-
 	err = st_sensors_verify_id(indio_dev);
 	if (err < 0)
-		goto st_magn_power_off;
+		return err;
 
 	mdata->num_data_channels = ST_MAGN_NUMBER_DATA_CHANNELS;
 	indio_dev->channels = mdata->sensor_settings->ch;
@@ -520,11 +516,11 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
 
 	err = st_sensors_init_sensor(indio_dev, pdata);
 	if (err < 0)
-		goto st_magn_power_off;
+		return err;
 
 	err = st_magn_allocate_ring(indio_dev);
 	if (err < 0)
-		goto st_magn_power_off;
+		return err;
 
 	if (mdata->irq > 0) {
 		err = st_sensors_allocate_trigger(indio_dev,
@@ -547,9 +543,6 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
 		st_sensors_deallocate_trigger(indio_dev);
 st_magn_probe_trigger_error:
 	st_magn_deallocate_ring(indio_dev);
-st_magn_power_off:
-	st_sensors_power_disable(indio_dev);
-
 	return err;
 }
 EXPORT_SYMBOL(st_magn_common_probe);
@@ -558,8 +551,6 @@ void st_magn_common_remove(struct iio_dev *indio_dev)
 {
 	struct st_sensor_data *mdata = iio_priv(indio_dev);
 
-	st_sensors_power_disable(indio_dev);
-
 	iio_device_unregister(indio_dev);
 	if (mdata->irq > 0)
 		st_sensors_deallocate_trigger(indio_dev);
diff --git a/drivers/iio/magnetometer/st_magn_i2c.c b/drivers/iio/magnetometer/st_magn_i2c.c
index c6bb4ce77594..7a7ab27379fc 100644
--- a/drivers/iio/magnetometer/st_magn_i2c.c
+++ b/drivers/iio/magnetometer/st_magn_i2c.c
@@ -78,16 +78,28 @@ static int st_magn_i2c_probe(struct i2c_client *client,
 	if (err < 0)
 		return err;
 
+	err = st_sensors_power_enable(indio_dev);
+	if (err)
+		return err;
+
 	err = st_magn_common_probe(indio_dev);
 	if (err < 0)
-		return err;
+		goto st_magn_power_off;
 
 	return 0;
+
+st_magn_power_off:
+	st_sensors_power_disable(indio_dev);
+
+	return err;
 }
 
 static int st_magn_i2c_remove(struct i2c_client *client)
 {
 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	st_sensors_power_disable(indio_dev);
+
 	st_magn_common_remove(indio_dev);
 
 	return 0;
diff --git a/drivers/iio/magnetometer/st_magn_spi.c b/drivers/iio/magnetometer/st_magn_spi.c
index 3d08d74c367d..ee352f083c02 100644
--- a/drivers/iio/magnetometer/st_magn_spi.c
+++ b/drivers/iio/magnetometer/st_magn_spi.c
@@ -72,16 +72,28 @@ static int st_magn_spi_probe(struct spi_device *spi)
 	if (err < 0)
 		return err;
 
+	err = st_sensors_power_enable(indio_dev);
+	if (err)
+		return err;
+
 	err = st_magn_common_probe(indio_dev);
 	if (err < 0)
-		return err;
+		goto st_magn_power_off;
 
 	return 0;
+
+st_magn_power_off:
+	st_sensors_power_disable(indio_dev);
+
+	return err;
 }
 
 static int st_magn_spi_remove(struct spi_device *spi)
 {
 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+
+	st_sensors_power_disable(indio_dev);
+
 	st_magn_common_remove(indio_dev);
 
 	return 0;
diff --git a/drivers/iio/pressure/st_pressure_core.c b/drivers/iio/pressure/st_pressure_core.c
index 789a2928504a..7912b5a68395 100644
--- a/drivers/iio/pressure/st_pressure_core.c
+++ b/drivers/iio/pressure/st_pressure_core.c
@@ -689,13 +689,9 @@ int st_press_common_probe(struct iio_dev *indio_dev)
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &press_info;
 
-	err = st_sensors_power_enable(indio_dev);
-	if (err)
-		return err;
-
 	err = st_sensors_verify_id(indio_dev);
 	if (err < 0)
-		goto st_press_power_off;
+		return err;
 
 	/*
 	 * Skip timestamping channel while declaring available channels to
@@ -718,11 +714,11 @@ int st_press_common_probe(struct iio_dev *indio_dev)
 
 	err = st_sensors_init_sensor(indio_dev, pdata);
 	if (err < 0)
-		goto st_press_power_off;
+		return err;
 
 	err = st_press_allocate_ring(indio_dev);
 	if (err < 0)
-		goto st_press_power_off;
+		return err;
 
 	if (press_data->irq > 0) {
 		err = st_sensors_allocate_trigger(indio_dev,
@@ -745,9 +741,6 @@ int st_press_common_probe(struct iio_dev *indio_dev)
 		st_sensors_deallocate_trigger(indio_dev);
 st_press_probe_trigger_error:
 	st_press_deallocate_ring(indio_dev);
-st_press_power_off:
-	st_sensors_power_disable(indio_dev);
-
 	return err;
 }
 EXPORT_SYMBOL(st_press_common_probe);
@@ -756,8 +749,6 @@ void st_press_common_remove(struct iio_dev *indio_dev)
 {
 	struct st_sensor_data *press_data = iio_priv(indio_dev);
 
-	st_sensors_power_disable(indio_dev);
-
 	iio_device_unregister(indio_dev);
 	if (press_data->irq > 0)
 		st_sensors_deallocate_trigger(indio_dev);
diff --git a/drivers/iio/pressure/st_pressure_i2c.c b/drivers/iio/pressure/st_pressure_i2c.c
index 09c6903f99b8..f0a5af314ceb 100644
--- a/drivers/iio/pressure/st_pressure_i2c.c
+++ b/drivers/iio/pressure/st_pressure_i2c.c
@@ -98,16 +98,29 @@ static int st_press_i2c_probe(struct i2c_client *client,
 	if (ret < 0)
 		return ret;
 
+	ret = st_sensors_power_enable(indio_dev);
+	if (ret)
+		return ret;
+
 	ret = st_press_common_probe(indio_dev);
 	if (ret < 0)
-		return ret;
+		goto st_press_power_off;
 
 	return 0;
+
+st_press_power_off:
+	st_sensors_power_disable(indio_dev);
+
+	return ret;
 }
 
 static int st_press_i2c_remove(struct i2c_client *client)
 {
-	st_press_common_remove(i2c_get_clientdata(client));
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	st_sensors_power_disable(indio_dev);
+
+	st_press_common_remove(indio_dev);
 
 	return 0;
 }
diff --git a/drivers/iio/pressure/st_pressure_spi.c b/drivers/iio/pressure/st_pressure_spi.c
index b5ee3ec2764f..b48cf7d01cd7 100644
--- a/drivers/iio/pressure/st_pressure_spi.c
+++ b/drivers/iio/pressure/st_pressure_spi.c
@@ -82,16 +82,29 @@ static int st_press_spi_probe(struct spi_device *spi)
 	if (err < 0)
 		return err;
 
+	err = st_sensors_power_enable(indio_dev);
+	if (err)
+		return err;
+
 	err = st_press_common_probe(indio_dev);
 	if (err < 0)
-		return err;
+		goto st_press_power_off;
 
 	return 0;
+
+st_press_power_off:
+	st_sensors_power_disable(indio_dev);
+
+	return err;
 }
 
 static int st_press_spi_remove(struct spi_device *spi)
 {
-	st_press_common_remove(spi_get_drvdata(spi));
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+
+	st_sensors_power_disable(indio_dev);
+
+	st_press_common_remove(indio_dev);
 
 	return 0;
 }
-- 
2.30.2

Re: [PATCH v1 4/7] iio: st_sensors: Call st_sensors_power_enable() from bus drivers

[Jonathan Cameron]

On Wed, 14 Apr 2021 22:54:51 +0300
Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:

> In case we would initialize two IIO devices from one physical device,
> we shouldn't have a clash on regulators. That's why move
> st_sensors_power_enable() call from core to bus drivers.

Why is this a problem?  The two instances would double up and both get +
enable + disable the regulators.  However, that shouldn't matter as
they are reference counted anyway.

Perhaps an example?  Even in patch 6 I can only see that it is wasteful
to do it twice, rather than wrong as such.

Jonathan


> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  drivers/iio/accel/st_accel_core.c       | 21 +++++----------------
>  drivers/iio/accel/st_accel_i2c.c        | 17 +++++++++++++++--
>  drivers/iio/accel/st_accel_spi.c        | 17 +++++++++++++++--
>  drivers/iio/gyro/st_gyro_core.c         | 15 +++------------
>  drivers/iio/gyro/st_gyro_i2c.c          | 17 +++++++++++++++--
>  drivers/iio/gyro/st_gyro_spi.c          | 17 +++++++++++++++--
>  drivers/iio/magnetometer/st_magn_core.c | 15 +++------------
>  drivers/iio/magnetometer/st_magn_i2c.c  | 14 +++++++++++++-
>  drivers/iio/magnetometer/st_magn_spi.c  | 14 +++++++++++++-
>  drivers/iio/pressure/st_pressure_core.c | 15 +++------------
>  drivers/iio/pressure/st_pressure_i2c.c  | 17 +++++++++++++++--
>  drivers/iio/pressure/st_pressure_spi.c  | 17 +++++++++++++++--
>  12 files changed, 130 insertions(+), 66 deletions(-)
> 
> diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c
> index a1bd7e3b912e..5c258c1ca62d 100644
> --- a/drivers/iio/accel/st_accel_core.c
> +++ b/drivers/iio/accel/st_accel_core.c
> @@ -1260,13 +1260,9 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
>  	indio_dev->modes = INDIO_DIRECT_MODE;
>  	indio_dev->info = &accel_info;
>  
> -	err = st_sensors_power_enable(indio_dev);
> -	if (err)
> -		return err;
> -
>  	err = st_sensors_verify_id(indio_dev);
>  	if (err < 0)
> -		goto st_accel_power_off;
> +		return err;
>  
>  	adata->num_data_channels = ST_ACCEL_NUMBER_DATA_CHANNELS;
>  	indio_dev->num_channels = ST_SENSORS_NUMBER_ALL_CHANNELS;
> @@ -1275,10 +1271,8 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
>  	channels = devm_kmemdup(&indio_dev->dev,
>  				adata->sensor_settings->ch,
>  				channels_size, GFP_KERNEL);
> -	if (!channels) {
> -		err = -ENOMEM;
> -		goto st_accel_power_off;
> -	}
> +	if (!channels)
> +		return -ENOMEM;
>  
>  	if (apply_acpi_orientation(indio_dev, channels))
>  		dev_warn(&indio_dev->dev,
> @@ -1293,11 +1287,11 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
>  
>  	err = st_sensors_init_sensor(indio_dev, pdata);
>  	if (err < 0)
> -		goto st_accel_power_off;
> +		return err;
>  
>  	err = st_accel_allocate_ring(indio_dev);
>  	if (err < 0)
> -		goto st_accel_power_off;
> +		return err;
>  
>  	if (adata->irq > 0) {
>  		err = st_sensors_allocate_trigger(indio_dev,
> @@ -1320,9 +1314,6 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
>  		st_sensors_deallocate_trigger(indio_dev);
>  st_accel_probe_trigger_error:
>  	st_accel_deallocate_ring(indio_dev);
> -st_accel_power_off:
> -	st_sensors_power_disable(indio_dev);
> -
>  	return err;
>  }
>  EXPORT_SYMBOL(st_accel_common_probe);
> @@ -1331,8 +1322,6 @@ void st_accel_common_remove(struct iio_dev *indio_dev)
>  {
>  	struct st_sensor_data *adata = iio_priv(indio_dev);
>  
> -	st_sensors_power_disable(indio_dev);
> -
>  	iio_device_unregister(indio_dev);
>  	if (adata->irq > 0)
>  		st_sensors_deallocate_trigger(indio_dev);
> diff --git a/drivers/iio/accel/st_accel_i2c.c b/drivers/iio/accel/st_accel_i2c.c
> index 360e16f2cadb..95e305b88d5e 100644
> --- a/drivers/iio/accel/st_accel_i2c.c
> +++ b/drivers/iio/accel/st_accel_i2c.c
> @@ -174,16 +174,29 @@ static int st_accel_i2c_probe(struct i2c_client *client)
>  	if (ret < 0)
>  		return ret;
>  
> +	ret = st_sensors_power_enable(indio_dev);
> +	if (ret)
> +		return ret;
> +
>  	ret = st_accel_common_probe(indio_dev);
>  	if (ret < 0)
> -		return ret;
> +		goto st_accel_power_off;
>  
>  	return 0;
> +
> +st_accel_power_off:
> +	st_sensors_power_disable(indio_dev);
> +
> +	return ret;
>  }
>  
>  static int st_accel_i2c_remove(struct i2c_client *client)
>  {
> -	st_accel_common_remove(i2c_get_clientdata(client));
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> +	st_sensors_power_disable(indio_dev);
> +
> +	st_accel_common_remove(indio_dev);
>  
>  	return 0;
>  }
> diff --git a/drivers/iio/accel/st_accel_spi.c b/drivers/iio/accel/st_accel_spi.c
> index 568ff1bae0ee..83d3308ce5cc 100644
> --- a/drivers/iio/accel/st_accel_spi.c
> +++ b/drivers/iio/accel/st_accel_spi.c
> @@ -123,16 +123,29 @@ static int st_accel_spi_probe(struct spi_device *spi)
>  	if (err < 0)
>  		return err;
>  
> +	err = st_sensors_power_enable(indio_dev);
> +	if (err)
> +		return err;
> +
>  	err = st_accel_common_probe(indio_dev);
>  	if (err < 0)
> -		return err;
> +		goto st_accel_power_off;
>  
>  	return 0;
> +
> +st_accel_power_off:
> +	st_sensors_power_disable(indio_dev);
> +
> +	return err;
>  }
>  
>  static int st_accel_spi_remove(struct spi_device *spi)
>  {
> -	st_accel_common_remove(spi_get_drvdata(spi));
> +	struct iio_dev *indio_dev = spi_get_drvdata(spi);
> +
> +	st_sensors_power_disable(indio_dev);
> +
> +	st_accel_common_remove(indio_dev);
>  
>  	return 0;
>  }
> diff --git a/drivers/iio/gyro/st_gyro_core.c b/drivers/iio/gyro/st_gyro_core.c
> index e000504e1df4..ee3f0ea96ac5 100644
> --- a/drivers/iio/gyro/st_gyro_core.c
> +++ b/drivers/iio/gyro/st_gyro_core.c
> @@ -471,13 +471,9 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
>  	indio_dev->modes = INDIO_DIRECT_MODE;
>  	indio_dev->info = &gyro_info;
>  
> -	err = st_sensors_power_enable(indio_dev);
> -	if (err)
> -		return err;
> -
>  	err = st_sensors_verify_id(indio_dev);
>  	if (err < 0)
> -		goto st_gyro_power_off;
> +		return err;
>  
>  	gdata->num_data_channels = ST_GYRO_NUMBER_DATA_CHANNELS;
>  	indio_dev->channels = gdata->sensor_settings->ch;
> @@ -490,11 +486,11 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
>  
>  	err = st_sensors_init_sensor(indio_dev, pdata);
>  	if (err < 0)
> -		goto st_gyro_power_off;
> +		return err;
>  
>  	err = st_gyro_allocate_ring(indio_dev);
>  	if (err < 0)
> -		goto st_gyro_power_off;
> +		return err;
>  
>  	if (gdata->irq > 0) {
>  		err = st_sensors_allocate_trigger(indio_dev,
> @@ -517,9 +513,6 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
>  		st_sensors_deallocate_trigger(indio_dev);
>  st_gyro_probe_trigger_error:
>  	st_gyro_deallocate_ring(indio_dev);
> -st_gyro_power_off:
> -	st_sensors_power_disable(indio_dev);
> -
>  	return err;
>  }
>  EXPORT_SYMBOL(st_gyro_common_probe);
> @@ -528,8 +521,6 @@ void st_gyro_common_remove(struct iio_dev *indio_dev)
>  {
>  	struct st_sensor_data *gdata = iio_priv(indio_dev);
>  
> -	st_sensors_power_disable(indio_dev);
> -
>  	iio_device_unregister(indio_dev);
>  	if (gdata->irq > 0)
>  		st_sensors_deallocate_trigger(indio_dev);
> diff --git a/drivers/iio/gyro/st_gyro_i2c.c b/drivers/iio/gyro/st_gyro_i2c.c
> index 8190966e6ff0..a25cc0379e16 100644
> --- a/drivers/iio/gyro/st_gyro_i2c.c
> +++ b/drivers/iio/gyro/st_gyro_i2c.c
> @@ -86,16 +86,29 @@ static int st_gyro_i2c_probe(struct i2c_client *client,
>  	if (err < 0)
>  		return err;
>  
> +	err = st_sensors_power_enable(indio_dev);
> +	if (err)
> +		return err;
> +
>  	err = st_gyro_common_probe(indio_dev);
>  	if (err < 0)
> -		return err;
> +		goto st_gyro_power_off;
>  
>  	return 0;
> +
> +st_gyro_power_off:
> +	st_sensors_power_disable(indio_dev);
> +
> +	return err;
>  }
>  
>  static int st_gyro_i2c_remove(struct i2c_client *client)
>  {
> -	st_gyro_common_remove(i2c_get_clientdata(client));
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> +	st_sensors_power_disable(indio_dev);
> +
> +	st_gyro_common_remove(indio_dev);
>  
>  	return 0;
>  }
> diff --git a/drivers/iio/gyro/st_gyro_spi.c b/drivers/iio/gyro/st_gyro_spi.c
> index efb862763ca3..18d6a2aeda45 100644
> --- a/drivers/iio/gyro/st_gyro_spi.c
> +++ b/drivers/iio/gyro/st_gyro_spi.c
> @@ -90,16 +90,29 @@ static int st_gyro_spi_probe(struct spi_device *spi)
>  	if (err < 0)
>  		return err;
>  
> +	err = st_sensors_power_enable(indio_dev);
> +	if (err)
> +		return err;
> +
>  	err = st_gyro_common_probe(indio_dev);
>  	if (err < 0)
> -		return err;
> +		goto st_gyro_power_off;
>  
>  	return 0;
> +
> +st_gyro_power_off:
> +	st_sensors_power_disable(indio_dev);
> +
> +	return err;
>  }
>  
>  static int st_gyro_spi_remove(struct spi_device *spi)
>  {
> -	st_gyro_common_remove(spi_get_drvdata(spi));
> +	struct iio_dev *indio_dev = spi_get_drvdata(spi);
> +
> +	st_sensors_power_disable(indio_dev);
> +
> +	st_gyro_common_remove(indio_dev);
>  
>  	return 0;
>  }
> diff --git a/drivers/iio/magnetometer/st_magn_core.c b/drivers/iio/magnetometer/st_magn_core.c
> index cf3722e42419..018b2523edfe 100644
> --- a/drivers/iio/magnetometer/st_magn_core.c
> +++ b/drivers/iio/magnetometer/st_magn_core.c
> @@ -500,13 +500,9 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
>  	indio_dev->modes = INDIO_DIRECT_MODE;
>  	indio_dev->info = &magn_info;
>  
> -	err = st_sensors_power_enable(indio_dev);
> -	if (err)
> -		return err;
> -
>  	err = st_sensors_verify_id(indio_dev);
>  	if (err < 0)
> -		goto st_magn_power_off;
> +		return err;
>  
>  	mdata->num_data_channels = ST_MAGN_NUMBER_DATA_CHANNELS;
>  	indio_dev->channels = mdata->sensor_settings->ch;
> @@ -520,11 +516,11 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
>  
>  	err = st_sensors_init_sensor(indio_dev, pdata);
>  	if (err < 0)
> -		goto st_magn_power_off;
> +		return err;
>  
>  	err = st_magn_allocate_ring(indio_dev);
>  	if (err < 0)
> -		goto st_magn_power_off;
> +		return err;
>  
>  	if (mdata->irq > 0) {
>  		err = st_sensors_allocate_trigger(indio_dev,
> @@ -547,9 +543,6 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
>  		st_sensors_deallocate_trigger(indio_dev);
>  st_magn_probe_trigger_error:
>  	st_magn_deallocate_ring(indio_dev);
> -st_magn_power_off:
> -	st_sensors_power_disable(indio_dev);
> -
>  	return err;
>  }
>  EXPORT_SYMBOL(st_magn_common_probe);
> @@ -558,8 +551,6 @@ void st_magn_common_remove(struct iio_dev *indio_dev)
>  {
>  	struct st_sensor_data *mdata = iio_priv(indio_dev);
>  
> -	st_sensors_power_disable(indio_dev);
> -
>  	iio_device_unregister(indio_dev);
>  	if (mdata->irq > 0)
>  		st_sensors_deallocate_trigger(indio_dev);
> diff --git a/drivers/iio/magnetometer/st_magn_i2c.c b/drivers/iio/magnetometer/st_magn_i2c.c
> index c6bb4ce77594..7a7ab27379fc 100644
> --- a/drivers/iio/magnetometer/st_magn_i2c.c
> +++ b/drivers/iio/magnetometer/st_magn_i2c.c
> @@ -78,16 +78,28 @@ static int st_magn_i2c_probe(struct i2c_client *client,
>  	if (err < 0)
>  		return err;
>  
> +	err = st_sensors_power_enable(indio_dev);
> +	if (err)
> +		return err;
> +
>  	err = st_magn_common_probe(indio_dev);
>  	if (err < 0)
> -		return err;
> +		goto st_magn_power_off;
>  
>  	return 0;
> +
> +st_magn_power_off:
> +	st_sensors_power_disable(indio_dev);
> +
> +	return err;
>  }
>  
>  static int st_magn_i2c_remove(struct i2c_client *client)
>  {
>  	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> +	st_sensors_power_disable(indio_dev);
> +
>  	st_magn_common_remove(indio_dev);
>  
>  	return 0;
> diff --git a/drivers/iio/magnetometer/st_magn_spi.c b/drivers/iio/magnetometer/st_magn_spi.c
> index 3d08d74c367d..ee352f083c02 100644
> --- a/drivers/iio/magnetometer/st_magn_spi.c
> +++ b/drivers/iio/magnetometer/st_magn_spi.c
> @@ -72,16 +72,28 @@ static int st_magn_spi_probe(struct spi_device *spi)
>  	if (err < 0)
>  		return err;
>  
> +	err = st_sensors_power_enable(indio_dev);
> +	if (err)
> +		return err;
> +
>  	err = st_magn_common_probe(indio_dev);
>  	if (err < 0)
> -		return err;
> +		goto st_magn_power_off;
>  
>  	return 0;
> +
> +st_magn_power_off:
> +	st_sensors_power_disable(indio_dev);
> +
> +	return err;
>  }
>  
>  static int st_magn_spi_remove(struct spi_device *spi)
>  {
>  	struct iio_dev *indio_dev = spi_get_drvdata(spi);
> +
> +	st_sensors_power_disable(indio_dev);
> +
>  	st_magn_common_remove(indio_dev);
>  
>  	return 0;
> diff --git a/drivers/iio/pressure/st_pressure_core.c b/drivers/iio/pressure/st_pressure_core.c
> index 789a2928504a..7912b5a68395 100644
> --- a/drivers/iio/pressure/st_pressure_core.c
> +++ b/drivers/iio/pressure/st_pressure_core.c
> @@ -689,13 +689,9 @@ int st_press_common_probe(struct iio_dev *indio_dev)
>  	indio_dev->modes = INDIO_DIRECT_MODE;
>  	indio_dev->info = &press_info;
>  
> -	err = st_sensors_power_enable(indio_dev);
> -	if (err)
> -		return err;
> -
>  	err = st_sensors_verify_id(indio_dev);
>  	if (err < 0)
> -		goto st_press_power_off;
> +		return err;
>  
>  	/*
>  	 * Skip timestamping channel while declaring available channels to
> @@ -718,11 +714,11 @@ int st_press_common_probe(struct iio_dev *indio_dev)
>  
>  	err = st_sensors_init_sensor(indio_dev, pdata);
>  	if (err < 0)
> -		goto st_press_power_off;
> +		return err;
>  
>  	err = st_press_allocate_ring(indio_dev);
>  	if (err < 0)
> -		goto st_press_power_off;
> +		return err;
>  
>  	if (press_data->irq > 0) {
>  		err = st_sensors_allocate_trigger(indio_dev,
> @@ -745,9 +741,6 @@ int st_press_common_probe(struct iio_dev *indio_dev)
>  		st_sensors_deallocate_trigger(indio_dev);
>  st_press_probe_trigger_error:
>  	st_press_deallocate_ring(indio_dev);
> -st_press_power_off:
> -	st_sensors_power_disable(indio_dev);
> -
>  	return err;
>  }
>  EXPORT_SYMBOL(st_press_common_probe);
> @@ -756,8 +749,6 @@ void st_press_common_remove(struct iio_dev *indio_dev)
>  {
>  	struct st_sensor_data *press_data = iio_priv(indio_dev);
>  
> -	st_sensors_power_disable(indio_dev);
> -
>  	iio_device_unregister(indio_dev);
>  	if (press_data->irq > 0)
>  		st_sensors_deallocate_trigger(indio_dev);
> diff --git a/drivers/iio/pressure/st_pressure_i2c.c b/drivers/iio/pressure/st_pressure_i2c.c
> index 09c6903f99b8..f0a5af314ceb 100644
> --- a/drivers/iio/pressure/st_pressure_i2c.c
> +++ b/drivers/iio/pressure/st_pressure_i2c.c
> @@ -98,16 +98,29 @@ static int st_press_i2c_probe(struct i2c_client *client,
>  	if (ret < 0)
>  		return ret;
>  
> +	ret = st_sensors_power_enable(indio_dev);
> +	if (ret)
> +		return ret;
> +
>  	ret = st_press_common_probe(indio_dev);
>  	if (ret < 0)
> -		return ret;
> +		goto st_press_power_off;
>  
>  	return 0;
> +
> +st_press_power_off:
> +	st_sensors_power_disable(indio_dev);
> +
> +	return ret;
>  }
>  
>  static int st_press_i2c_remove(struct i2c_client *client)
>  {
> -	st_press_common_remove(i2c_get_clientdata(client));
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> +	st_sensors_power_disable(indio_dev);
> +
> +	st_press_common_remove(indio_dev);
>  
>  	return 0;
>  }
> diff --git a/drivers/iio/pressure/st_pressure_spi.c b/drivers/iio/pressure/st_pressure_spi.c
> index b5ee3ec2764f..b48cf7d01cd7 100644
> --- a/drivers/iio/pressure/st_pressure_spi.c
> +++ b/drivers/iio/pressure/st_pressure_spi.c
> @@ -82,16 +82,29 @@ static int st_press_spi_probe(struct spi_device *spi)
>  	if (err < 0)
>  		return err;
>  
> +	err = st_sensors_power_enable(indio_dev);
> +	if (err)
> +		return err;
> +
>  	err = st_press_common_probe(indio_dev);
>  	if (err < 0)
> -		return err;
> +		goto st_press_power_off;
>  
>  	return 0;
> +
> +st_press_power_off:
> +	st_sensors_power_disable(indio_dev);
> +
> +	return err;
>  }
>  
>  static int st_press_spi_remove(struct spi_device *spi)
>  {
> -	st_press_common_remove(spi_get_drvdata(spi));
> +	struct iio_dev *indio_dev = spi_get_drvdata(spi);
> +
> +	st_sensors_power_disable(indio_dev);
> +
> +	st_press_common_remove(indio_dev);
>  
>  	return 0;
>  }

Re: [PATCH v1 4/7] iio: st_sensors: Call st_sensors_power_enable() from bus drivers

[Andy Shevchenko]

On Sun, Apr 18, 2021 at 1:54 PM Jonathan Cameron <jic23@kernel.org> wrote:
> On Wed, 14 Apr 2021 22:54:51 +0300
> Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
>
> > In case we would initialize two IIO devices from one physical device,
> > we shouldn't have a clash on regulators. That's why move
> > st_sensors_power_enable() call from core to bus drivers.
>
> Why is this a problem?

You can't have two regulators of the same name on the same device.
IIRC the regulator framework produces a good splat for this.

>  The two instances would double up and both get +
> enable + disable the regulators.  However, that shouldn't matter as
> they are reference counted anyway.
>
> Perhaps an example?  Even in patch 6 I can only see that it is wasteful
> to do it twice, rather than wrong as such.

Believe me, I would like to avoid that, but it seems a limitation of
the regulator framework. It simply produces a splat. I'll try to
reproduce it again (because this series started like a couple of years
ago, just eventually I found a time to clean up and submit) and will
tell you how it is going.


-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v1 4/7] iio: st_sensors: Call st_sensors_power_enable() from bus drivers

[Andy Shevchenko]

On Sun, Apr 18, 2021 at 1:54 PM Jonathan Cameron <jic23@kernel.org> wrote:
>
> On Wed, 14 Apr 2021 22:54:51 +0300
> Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
>
> > In case we would initialize two IIO devices from one physical device,
> > we shouldn't have a clash on regulators. That's why move
> > st_sensors_power_enable() call from core to bus drivers.
>
> Why is this a problem?  The two instances would double up and both get +
> enable + disable the regulators.  However, that shouldn't matter as
> they are reference counted anyway.

> Perhaps an example?  Even in patch 6 I can only see that it is wasteful
> to do it twice, rather than wrong as such.

Yep, now I also understand that I do it twice after this patch. But
lemme check next week this all

P.S. I have real hardware to test on. But my tests I guess are limited
to iio_info or so.

-- 
With Best Regards,
Andy Shevchenko

[PATCH v1 5/7] iio: st_sensors: Make accel, gyro, magn and pressure probe shared

[Andy Shevchenko]

Some IMUs may utilize existing library code for STMicro accelerometer,
gyroscope, magnetometer and pressure. Let's share them via st_sensors.h.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/iio/accel/st_accel.h          |  4 ----
 drivers/iio/gyro/st_gyro.h            |  4 ----
 drivers/iio/magnetometer/st_magn.h    |  4 ----
 drivers/iio/pressure/st_pressure.h    |  4 ----
 include/linux/iio/common/st_sensors.h | 20 ++++++++++++++++++++
 5 files changed, 20 insertions(+), 16 deletions(-)

diff --git a/drivers/iio/accel/st_accel.h b/drivers/iio/accel/st_accel.h
index 181ebe79c4eb..f5b0b8bbaff7 100644
--- a/drivers/iio/accel/st_accel.h
+++ b/drivers/iio/accel/st_accel.h
@@ -62,10 +62,6 @@ enum st_accel_type {
 #define LIS2DE12_ACCEL_DEV_NAME		"lis2de12"
 #define LIS2HH12_ACCEL_DEV_NAME		"lis2hh12"
 
-const struct st_sensor_settings *st_accel_get_settings(const char *name);
-int st_accel_common_probe(struct iio_dev *indio_dev);
-void st_accel_common_remove(struct iio_dev *indio_dev);
-
 #ifdef CONFIG_IIO_BUFFER
 int st_accel_allocate_ring(struct iio_dev *indio_dev);
 void st_accel_deallocate_ring(struct iio_dev *indio_dev);
diff --git a/drivers/iio/gyro/st_gyro.h b/drivers/iio/gyro/st_gyro.h
index b385fe664dcc..6537f5cb8320 100644
--- a/drivers/iio/gyro/st_gyro.h
+++ b/drivers/iio/gyro/st_gyro.h
@@ -24,10 +24,6 @@
 #define LSM330_GYRO_DEV_NAME		"lsm330_gyro"
 #define LSM9DS0_GYRO_DEV_NAME		"lsm9ds0_gyro"
 
-const struct st_sensor_settings *st_gyro_get_settings(const char *name);
-int st_gyro_common_probe(struct iio_dev *indio_dev);
-void st_gyro_common_remove(struct iio_dev *indio_dev);
-
 #ifdef CONFIG_IIO_BUFFER
 int st_gyro_allocate_ring(struct iio_dev *indio_dev);
 void st_gyro_deallocate_ring(struct iio_dev *indio_dev);
diff --git a/drivers/iio/magnetometer/st_magn.h b/drivers/iio/magnetometer/st_magn.h
index 204b285725c8..143b6fb4ae8d 100644
--- a/drivers/iio/magnetometer/st_magn.h
+++ b/drivers/iio/magnetometer/st_magn.h
@@ -22,10 +22,6 @@
 #define LIS2MDL_MAGN_DEV_NAME		"lis2mdl"
 #define LSM9DS1_MAGN_DEV_NAME		"lsm9ds1_magn"
 
-const struct st_sensor_settings *st_magn_get_settings(const char *name);
-int st_magn_common_probe(struct iio_dev *indio_dev);
-void st_magn_common_remove(struct iio_dev *indio_dev);
-
 #ifdef CONFIG_IIO_BUFFER
 int st_magn_allocate_ring(struct iio_dev *indio_dev);
 void st_magn_deallocate_ring(struct iio_dev *indio_dev);
diff --git a/drivers/iio/pressure/st_pressure.h b/drivers/iio/pressure/st_pressure.h
index 5c746ff6087e..9417b3bd7513 100644
--- a/drivers/iio/pressure/st_pressure.h
+++ b/drivers/iio/pressure/st_pressure.h
@@ -41,10 +41,6 @@ static __maybe_unused const struct st_sensors_platform_data default_press_pdata
 	.drdy_int_pin = 1,
 };
 
-const struct st_sensor_settings *st_press_get_settings(const char *name);
-int st_press_common_probe(struct iio_dev *indio_dev);
-void st_press_common_remove(struct iio_dev *indio_dev);
-
 #ifdef CONFIG_IIO_BUFFER
 int st_press_allocate_ring(struct iio_dev *indio_dev);
 void st_press_deallocate_ring(struct iio_dev *indio_dev);
diff --git a/include/linux/iio/common/st_sensors.h b/include/linux/iio/common/st_sensors.h
index 33e939977444..aa017b90fb06 100644
--- a/include/linux/iio/common/st_sensors.h
+++ b/include/linux/iio/common/st_sensors.h
@@ -317,4 +317,24 @@ ssize_t st_sensors_sysfs_scale_avail(struct device *dev,
 
 void st_sensors_dev_name_probe(struct device *dev, char *name, int len);
 
+/* Accelerometer */
+const struct st_sensor_settings *st_accel_get_settings(const char *name);
+int st_accel_common_probe(struct iio_dev *indio_dev);
+void st_accel_common_remove(struct iio_dev *indio_dev);
+
+/* Gyroscope */
+const struct st_sensor_settings *st_gyro_get_settings(const char *name);
+int st_gyro_common_probe(struct iio_dev *indio_dev);
+void st_gyro_common_remove(struct iio_dev *indio_dev);
+
+/* Magnetometer */
+const struct st_sensor_settings *st_magn_get_settings(const char *name);
+int st_magn_common_probe(struct iio_dev *indio_dev);
+void st_magn_common_remove(struct iio_dev *indio_dev);
+
+/* Pressure */
+const struct st_sensor_settings *st_press_get_settings(const char *name);
+int st_press_common_probe(struct iio_dev *indio_dev);
+void st_press_common_remove(struct iio_dev *indio_dev);
+
 #endif /* ST_SENSORS_H */
-- 
2.30.2

[PATCH v1 6/7] iio: st_sensors: Add lsm9ds0 IMU support

[Andy Shevchenko]

We can utilize separate drivers for accelerometer and magnetometer,
so here is the glue driver to enable LSM9DS0 IMU support.

The idea was suggested by Crestez Dan Leonard in [1]. The proposed change
was sent as RFC due to race condition concerns, which are indeed possible.

In order to amend the initial change, I went further by providing a specific
multi-instantiate probe driver that reuses existing accelerometer and
magnetometer.

[1]: https://lore.kernel.org/patchwork/patch/670353/

Suggested-by: Crestez Dan Leonard <leonard.crestez@intel.com>
Cc: mr.lahorde@laposte.net
Cc: Matija Podravec <matija_podravec@fastmail.fm>
Cc: Sergey Borishchenko <borischenko.sergey@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/iio/accel/st_accel_core.c            |  89 +++++++++-
 drivers/iio/imu/Kconfig                      |   1 +
 drivers/iio/imu/Makefile                     |   1 +
 drivers/iio/imu/st_lsm9ds0/Kconfig           |  28 ++++
 drivers/iio/imu/st_lsm9ds0/Makefile          |   5 +
 drivers/iio/imu/st_lsm9ds0/st_lsm9ds0.h      |  23 +++
 drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_core.c | 163 +++++++++++++++++++
 drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_i2c.c  |  84 ++++++++++
 drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_spi.c  |  83 ++++++++++
 drivers/iio/magnetometer/st_magn_core.c      |  98 +++++++++++
 include/linux/iio/common/st_sensors.h        |   2 +
 11 files changed, 576 insertions(+), 1 deletion(-)
 create mode 100644 drivers/iio/imu/st_lsm9ds0/Kconfig
 create mode 100644 drivers/iio/imu/st_lsm9ds0/Makefile
 create mode 100644 drivers/iio/imu/st_lsm9ds0/st_lsm9ds0.h
 create mode 100644 drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_core.c
 create mode 100644 drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_i2c.c
 create mode 100644 drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_spi.c

diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c
index 5c258c1ca62d..dc32ebefe3fc 100644
--- a/drivers/iio/accel/st_accel_core.c
+++ b/drivers/iio/accel/st_accel_core.c
@@ -980,7 +980,94 @@ static const struct st_sensor_settings st_accel_sensors_settings[] = {
 		.multi_read_bit = true,
 		.bootime = 2,
 	},
-
+	{
+		.wai = 0x49,
+		.wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
+		.sensors_supported = {
+			[0] = LSM9DS0_IMU_DEV_NAME,
+		},
+		.ch = (struct iio_chan_spec *)st_accel_16bit_channels,
+		.odr = {
+			.addr = 0x20,
+			.mask = GENMASK(7, 4),
+			.odr_avl = {
+				{ 3, 0x01, },
+				{ 6, 0x02, },
+				{ 12, 0x03, },
+				{ 25, 0x04, },
+				{ 50, 0x05, },
+				{ 100, 0x06, },
+				{ 200, 0x07, },
+				{ 400, 0x08, },
+				{ 800, 0x09, },
+				{ 1600, 0x0a, },
+			},
+		},
+		.pw = {
+			.addr = 0x20,
+			.mask = GENMASK(7, 4),
+			.value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
+		},
+		.enable_axis = {
+			.addr = ST_SENSORS_DEFAULT_AXIS_ADDR,
+			.mask = ST_SENSORS_DEFAULT_AXIS_MASK,
+		},
+		.fs = {
+			.addr = 0x21,
+			.mask = GENMASK(5, 3),
+			.fs_avl = {
+				[0] = {
+					.num = ST_ACCEL_FS_AVL_2G,
+					.value = 0x00,
+					.gain = IIO_G_TO_M_S_2(61),
+				},
+				[1] = {
+					.num = ST_ACCEL_FS_AVL_4G,
+					.value = 0x01,
+					.gain = IIO_G_TO_M_S_2(122),
+				},
+				[2] = {
+					.num = ST_ACCEL_FS_AVL_6G,
+					.value = 0x02,
+					.gain = IIO_G_TO_M_S_2(183),
+				},
+				[3] = {
+					.num = ST_ACCEL_FS_AVL_8G,
+					.value = 0x03,
+					.gain = IIO_G_TO_M_S_2(244),
+				},
+				[4] = {
+					.num = ST_ACCEL_FS_AVL_16G,
+					.value = 0x04,
+					.gain = IIO_G_TO_M_S_2(732),
+				},
+			},
+		},
+		.bdu = {
+			.addr = 0x20,
+			.mask = BIT(3),
+		},
+		.drdy_irq = {
+			.int1 = {
+				.addr = 0x22,
+				.mask = BIT(2),
+			},
+			.int2 = {
+				.addr = 0x23,
+				.mask = BIT(3),
+			},
+			.stat_drdy = {
+				.addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+				.mask = GENMASK(2, 0),
+			},
+		},
+		.sim = {
+			.addr = 0x21,
+			.value = BIT(0),
+		},
+		.multi_read_bit = true,
+		.bootime = 2,
+	},
 };
 
 /* Default accel DRDY is available on INT1 pin */
diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
index f02883b08480..001ca2c3ff95 100644
--- a/drivers/iio/imu/Kconfig
+++ b/drivers/iio/imu/Kconfig
@@ -94,6 +94,7 @@ config KMX61
 source "drivers/iio/imu/inv_icm42600/Kconfig"
 source "drivers/iio/imu/inv_mpu6050/Kconfig"
 source "drivers/iio/imu/st_lsm6dsx/Kconfig"
+source "drivers/iio/imu/st_lsm9ds0/Kconfig"
 
 endmenu
 
diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
index 13e9ff442b11..c82748096c77 100644
--- a/drivers/iio/imu/Makefile
+++ b/drivers/iio/imu/Makefile
@@ -26,3 +26,4 @@ obj-y += inv_mpu6050/
 obj-$(CONFIG_KMX61) += kmx61.o
 
 obj-y += st_lsm6dsx/
+obj-y += st_lsm9ds0/
diff --git a/drivers/iio/imu/st_lsm9ds0/Kconfig b/drivers/iio/imu/st_lsm9ds0/Kconfig
new file mode 100644
index 000000000000..53b7017014f8
--- /dev/null
+++ b/drivers/iio/imu/st_lsm9ds0/Kconfig
@@ -0,0 +1,28 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+config IIO_ST_LSM9DS0
+	tristate "STMicroelectronics LSM9DS0 IMU driver"
+	depends on (I2C || SPI_MASTER) && SYSFS
+	depends on !SENSORS_LIS3_I2C
+	depends on !SENSORS_LIS3_SPI
+	select IIO_ST_LSM9DS0_I2C if I2C
+	select IIO_ST_LSM9DS0_SPI if SPI_MASTER
+	select IIO_ST_ACCEL_3AXIS
+	select IIO_ST_MAGN_3AXIS
+
+	help
+	  Say yes here to build support for STMicroelectronics LSM9DS0 IMU
+	  sensor. Supported devices: accelerometer/magnetometer of lsm9ds0.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called st_lsm9ds0.
+
+config IIO_ST_LSM9DS0_I2C
+	tristate
+	depends on IIO_ST_LSM9DS0
+	select REGMAP_I2C
+
+config IIO_ST_LSM9DS0_SPI
+	tristate
+	depends on IIO_ST_LSM9DS0
+	select REGMAP_SPI
diff --git a/drivers/iio/imu/st_lsm9ds0/Makefile b/drivers/iio/imu/st_lsm9ds0/Makefile
new file mode 100644
index 000000000000..488af523f648
--- /dev/null
+++ b/drivers/iio/imu/st_lsm9ds0/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_IIO_ST_LSM9DS0) += st_lsm9ds0.o
+st_lsm9ds0-y := st_lsm9ds0_core.o
+obj-$(CONFIG_IIO_ST_LSM9DS0_I2C) += st_lsm9ds0_i2c.o
+obj-$(CONFIG_IIO_ST_LSM9DS0_SPI) += st_lsm9ds0_spi.o
diff --git a/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0.h b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0.h
new file mode 100644
index 000000000000..146393afd9a7
--- /dev/null
+++ b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+// STMicroelectronics LSM9DS0 IMU driver
+
+#ifndef ST_LSM9DS0_H
+#define ST_LSM9DS0_H
+
+struct iio_dev;
+struct regulator;
+
+struct st_lsm9ds0 {
+	struct device *dev;
+	const char *name;
+	int irq;
+	struct iio_dev *accel;
+	struct iio_dev *magn;
+	struct regulator *vdd;
+	struct regulator *vdd_io;
+};
+
+int st_lsm9ds0_probe(struct st_lsm9ds0 *lsm9ds0, struct regmap *regmap);
+int st_lsm9ds0_remove(struct st_lsm9ds0 *lsm9ds0);
+
+#endif /* ST_LSM9DS0_H */
diff --git a/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_core.c b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_core.c
new file mode 100644
index 000000000000..8204f7303fd7
--- /dev/null
+++ b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_core.c
@@ -0,0 +1,163 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * STMicroelectronics LSM9DS0 IMU driver
+ *
+ * Copyright (C) 2021, Intel Corporation
+ *
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+
+#include <linux/iio/common/st_sensors.h>
+#include <linux/iio/iio.h>
+
+#include "st_lsm9ds0.h"
+
+static int st_lsm9ds0_power_enable(struct device *dev, struct st_lsm9ds0 *lsm9ds0)
+{
+	int ret;
+
+	/* Regulators not mandatory, but if requested we should enable them. */
+	lsm9ds0->vdd = devm_regulator_get(dev, "vdd");
+	if (IS_ERR(lsm9ds0->vdd)) {
+		dev_err(dev, "unable to get Vdd supply\n");
+		return PTR_ERR(lsm9ds0->vdd);
+	}
+	ret = regulator_enable(lsm9ds0->vdd);
+	if (ret) {
+		dev_warn(dev, "Failed to enable specified Vdd supply\n");
+		return ret;
+	}
+
+	lsm9ds0->vdd_io = devm_regulator_get(dev, "vddio");
+	if (IS_ERR(lsm9ds0->vdd_io)) {
+		dev_err(dev, "unable to get Vdd_IO supply\n");
+		regulator_disable(lsm9ds0->vdd);
+		return PTR_ERR(lsm9ds0->vdd_io);
+	}
+	ret = regulator_enable(lsm9ds0->vdd_io);
+	if (ret) {
+		dev_warn(dev, "Failed to enable specified Vdd_IO supply\n");
+		regulator_disable(lsm9ds0->vdd);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void st_lsm9ds0_power_disable(void *data)
+{
+	struct st_lsm9ds0 *lsm9ds0 = data;
+
+	regulator_disable(lsm9ds0->vdd_io);
+	regulator_disable(lsm9ds0->vdd);
+}
+
+static int devm_st_lsm9ds0_power_enable(struct st_lsm9ds0 *lsm9ds0)
+{
+	struct device *dev = lsm9ds0->dev;
+	int ret;
+
+	ret = st_lsm9ds0_power_enable(dev, lsm9ds0);
+	if (ret)
+		return ret;
+
+	return devm_add_action_or_reset(dev, st_lsm9ds0_power_disable, lsm9ds0);
+}
+
+static int st_lsm9ds0_probe_accel(struct st_lsm9ds0 *lsm9ds0, struct regmap *regmap)
+{
+	const struct st_sensor_settings *settings;
+	struct device *dev = lsm9ds0->dev;
+	struct st_sensor_data *data;
+
+	settings = st_accel_get_settings(lsm9ds0->name);
+	if (!settings) {
+		dev_err(dev, "device name %s not recognized.\n", lsm9ds0->name);
+		return -ENODEV;
+	}
+
+	lsm9ds0->accel = devm_iio_device_alloc(dev, sizeof(*data));
+	if (!lsm9ds0->accel)
+		return -ENOMEM;
+
+	lsm9ds0->accel->name = lsm9ds0->name;
+
+	data = iio_priv(lsm9ds0->accel);
+	data->sensor_settings = (struct st_sensor_settings *)settings;
+	data->dev = dev;
+	data->irq = lsm9ds0->irq;
+	data->regmap = regmap;
+	data->vdd = lsm9ds0->vdd;
+	data->vdd_io = lsm9ds0->vdd_io;
+
+	return st_accel_common_probe(lsm9ds0->accel);
+}
+
+static int st_lsm9ds0_probe_magn(struct st_lsm9ds0 *lsm9ds0, struct regmap *regmap)
+{
+	const struct st_sensor_settings *settings;
+	struct device *dev = lsm9ds0->dev;
+	struct st_sensor_data *data;
+
+	settings = st_magn_get_settings(lsm9ds0->name);
+	if (!settings) {
+		dev_err(dev, "device name %s not recognized.\n", lsm9ds0->name);
+		return -ENODEV;
+	}
+
+	lsm9ds0->magn = devm_iio_device_alloc(dev, sizeof(*data));
+	if (!lsm9ds0->magn)
+		return -ENOMEM;
+
+	lsm9ds0->magn->name = lsm9ds0->name;
+
+	data = iio_priv(lsm9ds0->magn);
+	data->sensor_settings = (struct st_sensor_settings *)settings;
+	data->dev = dev;
+	data->irq = lsm9ds0->irq;
+	data->regmap = regmap;
+	data->vdd = lsm9ds0->vdd;
+	data->vdd_io = lsm9ds0->vdd_io;
+
+	return st_magn_common_probe(lsm9ds0->magn);
+}
+
+int st_lsm9ds0_probe(struct st_lsm9ds0 *lsm9ds0, struct regmap *regmap)
+{
+	int ret;
+
+	ret = devm_st_lsm9ds0_power_enable(lsm9ds0);
+	if (ret)
+		return ret;
+
+	/* Setup accelerometer device */
+	ret = st_lsm9ds0_probe_accel(lsm9ds0, regmap);
+	if (ret)
+		return ret;
+
+	/* Setup magnetometer device */
+	ret = st_lsm9ds0_probe_magn(lsm9ds0, regmap);
+	if (ret)
+		st_accel_common_remove(lsm9ds0->accel);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(st_lsm9ds0_probe);
+
+int st_lsm9ds0_remove(struct st_lsm9ds0 *lsm9ds0)
+{
+	st_magn_common_remove(lsm9ds0->magn);
+	st_accel_common_remove(lsm9ds0->accel);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(st_lsm9ds0_remove);
+
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
+MODULE_DESCRIPTION("STMicroelectronics LSM9DS0 IMU core driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_i2c.c b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_i2c.c
new file mode 100644
index 000000000000..50a36ab53bc3
--- /dev/null
+++ b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_i2c.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * STMicroelectronics LSM9DS0 IMU driver
+ *
+ * Copyright (C) 2021, Intel Corporation
+ *
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ */
+
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include <linux/iio/common/st_sensors_i2c.h>
+
+#include "st_lsm9ds0.h"
+
+static const struct of_device_id st_lsm9ds0_of_match[] = {
+	{
+		.compatible = "st,lsm9ds0-imu",
+		.data = LSM9DS0_IMU_DEV_NAME,
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, st_lsm9ds0_of_match);
+
+static const struct i2c_device_id st_lsm9ds0_id_table[] = {
+	{ LSM9DS0_IMU_DEV_NAME },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, st_lsm9ds0_id_table);
+
+static const struct regmap_config st_lsm9ds0_regmap_config = {
+	.reg_bits	= 8,
+	.val_bits	= 8,
+	.read_flag_mask	= 0x80,
+};
+
+static int st_lsm9ds0_i2c_probe(struct i2c_client *client)
+{
+	const struct regmap_config *config = &st_lsm9ds0_regmap_config;
+	struct device *dev = &client->dev;
+	struct st_lsm9ds0 *lsm9ds0;
+	struct regmap *regmap;
+
+	st_sensors_dev_name_probe(dev, client->name, sizeof(client->name));
+
+	lsm9ds0 = devm_kzalloc(dev, sizeof(*lsm9ds0), GFP_KERNEL);
+	if (!lsm9ds0)
+		return -ENOMEM;
+
+	lsm9ds0->dev = dev;
+	lsm9ds0->name = client->name;
+	lsm9ds0->irq = client->irq;
+
+	regmap = devm_regmap_init_i2c(client, config);
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
+
+	i2c_set_clientdata(client, lsm9ds0);
+
+	return st_lsm9ds0_probe(lsm9ds0, regmap);
+}
+
+static int st_lsm9ds0_i2c_remove(struct i2c_client *client)
+{
+	return st_lsm9ds0_remove(i2c_get_clientdata(client));
+}
+
+static struct i2c_driver st_lsm9ds0_driver = {
+	.driver = {
+		.name = "st-lsm9ds0-i2c",
+		.of_match_table = st_lsm9ds0_of_match,
+	},
+	.probe_new = st_lsm9ds0_i2c_probe,
+	.remove = st_lsm9ds0_i2c_remove,
+	.id_table = st_lsm9ds0_id_table,
+};
+module_i2c_driver(st_lsm9ds0_driver);
+
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
+MODULE_DESCRIPTION("STMicroelectronics LSM9DS0 IMU I2C driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_spi.c b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_spi.c
new file mode 100644
index 000000000000..272c88990dd0
--- /dev/null
+++ b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_spi.c
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * STMicroelectronics LSM9DS0 IMU driver
+ *
+ * Copyright (C) 2021, Intel Corporation
+ *
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+
+#include <linux/iio/common/st_sensors_spi.h>
+
+#include "st_lsm9ds0.h"
+
+static const struct of_device_id st_lsm9ds0_of_match[] = {
+	{
+		.compatible = "st,lsm9ds0-imu",
+		.data = LSM9DS0_IMU_DEV_NAME,
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, st_lsm9ds0_of_match);
+
+static const struct spi_device_id st_lsm9ds0_id_table[] = {
+	{ LSM9DS0_IMU_DEV_NAME },
+	{}
+};
+MODULE_DEVICE_TABLE(spi, st_lsm9ds0_id_table);
+
+static const struct regmap_config st_lsm9ds0_regmap_config = {
+	.reg_bits	= 8,
+	.val_bits	= 8,
+	.read_flag_mask	= 0xc0,
+};
+
+static int st_lsm9ds0_spi_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct st_lsm9ds0 *lsm9ds0;
+	struct regmap *regmap;
+
+	st_sensors_dev_name_probe(dev, spi->modalias, sizeof(spi->modalias));
+
+	lsm9ds0 = devm_kzalloc(dev, sizeof(*lsm9ds0), GFP_KERNEL);
+	if (!lsm9ds0)
+		return -ENOMEM;
+
+	lsm9ds0->dev = dev;
+	lsm9ds0->name = spi->modalias;
+	lsm9ds0->irq = spi->irq;
+
+	regmap = devm_regmap_init_spi(spi, &st_lsm9ds0_regmap_config);
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
+
+	spi_set_drvdata(spi, lsm9ds0);
+
+	return st_lsm9ds0_probe(lsm9ds0, regmap);
+}
+
+static int st_lsm9ds0_spi_remove(struct spi_device *spi)
+{
+	return st_lsm9ds0_remove(spi_get_drvdata(spi));
+}
+
+static struct spi_driver st_lsm9ds0_driver = {
+	.driver = {
+		.name = "st-lsm9ds0-spi",
+		.of_match_table = st_lsm9ds0_of_match,
+	},
+	.probe = st_lsm9ds0_spi_probe,
+	.remove = st_lsm9ds0_spi_remove,
+	.id_table = st_lsm9ds0_id_table,
+};
+module_spi_driver(st_lsm9ds0_driver);
+
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
+MODULE_DESCRIPTION("STMicroelectronics LSM9DS0 IMU SPI driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/magnetometer/st_magn_core.c b/drivers/iio/magnetometer/st_magn_core.c
index 018b2523edfe..34fd892a776a 100644
--- a/drivers/iio/magnetometer/st_magn_core.c
+++ b/drivers/iio/magnetometer/st_magn_core.c
@@ -33,6 +33,7 @@
 /* FULLSCALE */
 #define ST_MAGN_FS_AVL_1300MG			1300
 #define ST_MAGN_FS_AVL_1900MG			1900
+#define ST_MAGN_FS_AVL_2000MG			2000
 #define ST_MAGN_FS_AVL_2500MG			2500
 #define ST_MAGN_FS_AVL_4000MG			4000
 #define ST_MAGN_FS_AVL_4700MG			4700
@@ -53,6 +54,11 @@
 #define ST_MAGN_3_OUT_Y_L_ADDR			0x6a
 #define ST_MAGN_3_OUT_Z_L_ADDR			0x6c
 
+/* Special L addresses for sensor 4 */
+#define ST_MAGN_4_OUT_X_L_ADDR			0x08
+#define ST_MAGN_4_OUT_Y_L_ADDR			0x0a
+#define ST_MAGN_4_OUT_Z_L_ADDR			0x0c
+
 static const struct iio_chan_spec st_magn_16bit_channels[] = {
 	ST_SENSORS_LSM_CHANNELS(IIO_MAGN,
 			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
@@ -101,6 +107,22 @@ static const struct iio_chan_spec st_magn_3_16bit_channels[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(3)
 };
 
+static const struct iio_chan_spec st_magn_4_16bit_channels[] = {
+	ST_SENSORS_LSM_CHANNELS(IIO_MAGN,
+			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+			ST_SENSORS_SCAN_X, 1, IIO_MOD_X, 's', IIO_LE, 16, 16,
+			ST_MAGN_4_OUT_X_L_ADDR),
+	ST_SENSORS_LSM_CHANNELS(IIO_MAGN,
+			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+			ST_SENSORS_SCAN_Y, 1, IIO_MOD_Y, 's', IIO_LE, 16, 16,
+			ST_MAGN_4_OUT_Y_L_ADDR),
+	ST_SENSORS_LSM_CHANNELS(IIO_MAGN,
+			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+			ST_SENSORS_SCAN_Z, 1, IIO_MOD_Z, 's', IIO_LE, 16, 16,
+			ST_MAGN_4_OUT_Z_L_ADDR),
+	IIO_CHAN_SOFT_TIMESTAMP(3)
+};
+
 static const struct st_sensor_settings st_magn_sensors_settings[] = {
 	{
 		.wai = 0, /* This sensor has no valid WhoAmI report 0 */
@@ -380,6 +402,82 @@ static const struct st_sensor_settings st_magn_sensors_settings[] = {
 		.multi_read_bit = false,
 		.bootime = 2,
 	},
+	{
+		.wai = 0x49,
+		.wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
+		.sensors_supported = {
+			[0] = LSM9DS0_IMU_DEV_NAME,
+		},
+		.ch = (struct iio_chan_spec *)st_magn_4_16bit_channels,
+		.odr = {
+			.addr = 0x24,
+			.mask = GENMASK(4, 2),
+			.odr_avl = {
+				{ 3, 0x00, },
+				{ 6, 0x01, },
+				{ 12, 0x02, },
+				{ 25, 0x03, },
+				{ 50, 0x04, },
+				{ 100, 0x05, },
+			},
+		},
+		.pw = {
+			.addr = 0x26,
+			.mask = GENMASK(1, 0),
+			.value_on = 0x00,
+			.value_off = 0x03,
+		},
+		.fs = {
+			.addr = 0x25,
+			.mask = GENMASK(6, 5),
+			.fs_avl = {
+				[0] = {
+					.num = ST_MAGN_FS_AVL_2000MG,
+					.value = 0x00,
+					.gain = 73,
+				},
+				[1] = {
+					.num = ST_MAGN_FS_AVL_4000MG,
+					.value = 0x01,
+					.gain = 146,
+				},
+				[2] = {
+					.num = ST_MAGN_FS_AVL_8000MG,
+					.value = 0x02,
+					.gain = 292,
+				},
+				[3] = {
+					.num = ST_MAGN_FS_AVL_12000MG,
+					.value = 0x03,
+					.gain = 438,
+				},
+			},
+		},
+		.bdu = {
+			.addr = 0x20,
+			.mask = BIT(3),
+		},
+		.drdy_irq = {
+			.int1 = {
+				.addr = 0x22,
+				.mask = BIT(1),
+			},
+			.int2 = {
+				.addr = 0x23,
+				.mask = BIT(2),
+			},
+			.stat_drdy = {
+				.addr = 0x07,
+				.mask = GENMASK(2, 0),
+			},
+		},
+		.sim = {
+			.addr = 0x21,
+			.value = BIT(0),
+		},
+		.multi_read_bit = true,
+		.bootime = 2,
+	},
 };
 
 /* Default magn DRDY is available on INT2 pin */
diff --git a/include/linux/iio/common/st_sensors.h b/include/linux/iio/common/st_sensors.h
index aa017b90fb06..0b9aeb479f48 100644
--- a/include/linux/iio/common/st_sensors.h
+++ b/include/linux/iio/common/st_sensors.h
@@ -20,6 +20,8 @@
 
 #include <linux/platform_data/st_sensors_pdata.h>
 
+#define LSM9DS0_IMU_DEV_NAME		"lsm9ds0"
+
 /*
  * Buffer size max case: 2bytes per channel, 3 channels in total +
  *			 8bytes timestamp channel (s64)
-- 
2.30.2

Re: [PATCH v1 6/7] iio: st_sensors: Add lsm9ds0 IMU support

[Jonathan Cameron]

On Wed, 14 Apr 2021 22:54:53 +0300
Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:

> We can utilize separate drivers for accelerometer and magnetometer,
> so here is the glue driver to enable LSM9DS0 IMU support.
> 
> The idea was suggested by Crestez Dan Leonard in [1]. The proposed change
> was sent as RFC due to race condition concerns, which are indeed possible.

If you are going to mention races, good to give some flavour in here!


This driver makes me very nervous indeed.  I haven't 'found' any places
where the fact we'll write the same registers from each of the drivers
causes problems (e.g. int pin setup etc) but perhaps I'm missing something.

Shall we say that makes me rather keener to get eyes (and thought) on this
patch than normal :)


> 
> In order to amend the initial change, I went further by providing a specific
> multi-instantiate probe driver that reuses existing accelerometer and
> magnetometer.
> 
> [1]: https://lore.kernel.org/patchwork/patch/670353/
> 
> Suggested-by: Crestez Dan Leonard <leonard.crestez@intel.com>
> Cc: mr.lahorde@laposte.net
> Cc: Matija Podravec <matija_podravec@fastmail.fm>
> Cc: Sergey Borishchenko <borischenko.sergey@gmail.com>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

A few comments in here, though mostly about stuff related to the origin code
you are copying so perhaps not tidying them up is preferable because it would
complicate comparison of the two cases.
> ---
>  drivers/iio/accel/st_accel_core.c            |  89 +++++++++-
>  drivers/iio/imu/Kconfig                      |   1 +
>  drivers/iio/imu/Makefile                     |   1 +
>  drivers/iio/imu/st_lsm9ds0/Kconfig           |  28 ++++
>  drivers/iio/imu/st_lsm9ds0/Makefile          |   5 +
>  drivers/iio/imu/st_lsm9ds0/st_lsm9ds0.h      |  23 +++
>  drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_core.c | 163 +++++++++++++++++++
>  drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_i2c.c  |  84 ++++++++++
>  drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_spi.c  |  83 ++++++++++
>  drivers/iio/magnetometer/st_magn_core.c      |  98 +++++++++++
>  include/linux/iio/common/st_sensors.h        |   2 +
>  11 files changed, 576 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/iio/imu/st_lsm9ds0/Kconfig
>  create mode 100644 drivers/iio/imu/st_lsm9ds0/Makefile
>  create mode 100644 drivers/iio/imu/st_lsm9ds0/st_lsm9ds0.h
>  create mode 100644 drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_core.c
>  create mode 100644 drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_i2c.c
>  create mode 100644 drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_spi.c
> 
> diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c
> index 5c258c1ca62d..dc32ebefe3fc 100644
> --- a/drivers/iio/accel/st_accel_core.c
> +++ b/drivers/iio/accel/st_accel_core.c
> @@ -980,7 +980,94 @@ static const struct st_sensor_settings st_accel_sensors_settings[] = {
>  		.multi_read_bit = true,
>  		.bootime = 2,
>  	},
> -
> +	{
> +		.wai = 0x49,
> +		.wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
> +		.sensors_supported = {
> +			[0] = LSM9DS0_IMU_DEV_NAME,

What does the name attribute report for these?

Previously we've had the _accel etc postfix to differentiate the devices. I don't
suppose it matters to much though as easy enough to identify the accelerometer
etc from what channels are present.

Of course driver may get name from somewhere different anyway, I haven't checked,
just noticed this was different and wondered what the affect might be.

>  
>  /* Default accel DRDY is available on INT1 pin */
> diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
> index f02883b08480..001ca2c3ff95 100644
> --- a/drivers/iio/imu/Kconfig
> +++ b/drivers/iio/imu/Kconfig
> @@ -94,6 +94,7 @@ config KMX61
>  source "drivers/iio/imu/inv_icm42600/Kconfig"
>  source "drivers/iio/imu/inv_mpu6050/Kconfig"
>  source "drivers/iio/imu/st_lsm6dsx/Kconfig"
> +source "drivers/iio/imu/st_lsm9ds0/Kconfig"
>  
>  endmenu
>  
> diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
> index 13e9ff442b11..c82748096c77 100644
> --- a/drivers/iio/imu/Makefile
> +++ b/drivers/iio/imu/Makefile
> @@ -26,3 +26,4 @@ obj-y += inv_mpu6050/
>  obj-$(CONFIG_KMX61) += kmx61.o
>  
>  obj-y += st_lsm6dsx/
> +obj-y += st_lsm9ds0/
> diff --git a/drivers/iio/imu/st_lsm9ds0/Kconfig b/drivers/iio/imu/st_lsm9ds0/Kconfig
> new file mode 100644
> index 000000000000..53b7017014f8
> --- /dev/null
> +++ b/drivers/iio/imu/st_lsm9ds0/Kconfig
> @@ -0,0 +1,28 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +
> +config IIO_ST_LSM9DS0
> +	tristate "STMicroelectronics LSM9DS0 IMU driver"
> +	depends on (I2C || SPI_MASTER) && SYSFS
> +	depends on !SENSORS_LIS3_I2C
> +	depends on !SENSORS_LIS3_SPI
> +	select IIO_ST_LSM9DS0_I2C if I2C
> +	select IIO_ST_LSM9DS0_SPI if SPI_MASTER
> +	select IIO_ST_ACCEL_3AXIS
> +	select IIO_ST_MAGN_3AXIS
> +
> +	help
> +	  Say yes here to build support for STMicroelectronics LSM9DS0 IMU
> +	  sensor. Supported devices: accelerometer/magnetometer of lsm9ds0.
> +
> +	  To compile this driver as a module, choose M here: the module
> +	  will be called st_lsm9ds0.
> +
> +config IIO_ST_LSM9DS0_I2C
> +	tristate
> +	depends on IIO_ST_LSM9DS0
> +	select REGMAP_I2C
> +
> +config IIO_ST_LSM9DS0_SPI
> +	tristate
> +	depends on IIO_ST_LSM9DS0
> +	select REGMAP_SPI
> diff --git a/drivers/iio/imu/st_lsm9ds0/Makefile b/drivers/iio/imu/st_lsm9ds0/Makefile
> new file mode 100644
> index 000000000000..488af523f648
> --- /dev/null
> +++ b/drivers/iio/imu/st_lsm9ds0/Makefile
> @@ -0,0 +1,5 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +obj-$(CONFIG_IIO_ST_LSM9DS0) += st_lsm9ds0.o
> +st_lsm9ds0-y := st_lsm9ds0_core.o
> +obj-$(CONFIG_IIO_ST_LSM9DS0_I2C) += st_lsm9ds0_i2c.o
> +obj-$(CONFIG_IIO_ST_LSM9DS0_SPI) += st_lsm9ds0_spi.o
> diff --git a/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0.h b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0.h
> new file mode 100644
> index 000000000000..146393afd9a7
> --- /dev/null
> +++ b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0.h
> @@ -0,0 +1,23 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +// STMicroelectronics LSM9DS0 IMU driver
> +
> +#ifndef ST_LSM9DS0_H
> +#define ST_LSM9DS0_H
> +
> +struct iio_dev;
> +struct regulator;
> +
> +struct st_lsm9ds0 {
> +	struct device *dev;
> +	const char *name;
> +	int irq;
> +	struct iio_dev *accel;
> +	struct iio_dev *magn;
> +	struct regulator *vdd;
> +	struct regulator *vdd_io;
> +};
> +
> +int st_lsm9ds0_probe(struct st_lsm9ds0 *lsm9ds0, struct regmap *regmap);
> +int st_lsm9ds0_remove(struct st_lsm9ds0 *lsm9ds0);
> +
> +#endif /* ST_LSM9DS0_H */
> diff --git a/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_core.c b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_core.c
> new file mode 100644
> index 000000000000..8204f7303fd7
> --- /dev/null
> +++ b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_core.c
> @@ -0,0 +1,163 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * STMicroelectronics LSM9DS0 IMU driver
> + *
> + * Copyright (C) 2021, Intel Corporation
> + *
> + * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> + */
> +
> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/module.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include <linux/iio/common/st_sensors.h>
> +#include <linux/iio/iio.h>
> +
> +#include "st_lsm9ds0.h"
> +
> +static int st_lsm9ds0_power_enable(struct device *dev, struct st_lsm9ds0 *lsm9ds0)
> +{
> +	int ret;
> +
> +	/* Regulators not mandatory, but if requested we should enable them. */

That's a bit of a missleading comment though cut and paste from the other driver
code.  Key is that they will be handled by stub regulators if we don't provide
the which is not really what that comment implies.
 
> +	lsm9ds0->vdd = devm_regulator_get(dev, "vdd");
> +	if (IS_ERR(lsm9ds0->vdd)) {
> +		dev_err(dev, "unable to get Vdd supply\n");
> +		return PTR_ERR(lsm9ds0->vdd);
> +	}
> +	ret = regulator_enable(lsm9ds0->vdd);
> +	if (ret) {
> +		dev_warn(dev, "Failed to enable specified Vdd supply\n");

Given we fail to probe if this is true, dev_warn seems a bit soft.

> +		return ret;
> +	}
> +
> +	lsm9ds0->vdd_io = devm_regulator_get(dev, "vddio");
> +	if (IS_ERR(lsm9ds0->vdd_io)) {
> +		dev_err(dev, "unable to get Vdd_IO supply\n");
> +		regulator_disable(lsm9ds0->vdd);
> +		return PTR_ERR(lsm9ds0->vdd_io);
> +	}
> +	ret = regulator_enable(lsm9ds0->vdd_io);
> +	if (ret) {
> +		dev_warn(dev, "Failed to enable specified Vdd_IO supply\n");
> +		regulator_disable(lsm9ds0->vdd);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
 +
> +static void st_lsm9ds0_power_disable(void *data)
> +{
> +	struct st_lsm9ds0 *lsm9ds0 = data;
> +
> +	regulator_disable(lsm9ds0->vdd_io);
> +	regulator_disable(lsm9ds0->vdd);
> +}
> +
> +static int devm_st_lsm9ds0_power_enable(struct st_lsm9ds0 *lsm9ds0)
> +{
> +	struct device *dev = lsm9ds0->dev;
> +	int ret;
> +
> +	ret = st_lsm9ds0_power_enable(dev, lsm9ds0);
> +	if (ret)
> +		return ret;
> +
> +	return devm_add_action_or_reset(dev, st_lsm9ds0_power_disable, lsm9ds0);
> +}
> +
> +static int st_lsm9ds0_probe_accel(struct st_lsm9ds0 *lsm9ds0, struct regmap *regmap)
> +{
> +	const struct st_sensor_settings *settings;
> +	struct device *dev = lsm9ds0->dev;
> +	struct st_sensor_data *data;
> +
> +	settings = st_accel_get_settings(lsm9ds0->name);
> +	if (!settings) {
> +		dev_err(dev, "device name %s not recognized.\n", lsm9ds0->name);
> +		return -ENODEV;
> +	}
> +
> +	lsm9ds0->accel = devm_iio_device_alloc(dev, sizeof(*data));
> +	if (!lsm9ds0->accel)
> +		return -ENOMEM;
> +
> +	lsm9ds0->accel->name = lsm9ds0->name;
> +
> +	data = iio_priv(lsm9ds0->accel);
> +	data->sensor_settings = (struct st_sensor_settings *)settings;
> +	data->dev = dev;
> +	data->irq = lsm9ds0->irq;
> +	data->regmap = regmap;
> +	data->vdd = lsm9ds0->vdd;
> +	data->vdd_io = lsm9ds0->vdd_io;
> +
> +	return st_accel_common_probe(lsm9ds0->accel);
> +}
> +
> +static int st_lsm9ds0_probe_magn(struct st_lsm9ds0 *lsm9ds0, struct regmap *regmap)
> +{
> +	const struct st_sensor_settings *settings;
> +	struct device *dev = lsm9ds0->dev;
> +	struct st_sensor_data *data;
> +
> +	settings = st_magn_get_settings(lsm9ds0->name);
> +	if (!settings) {
> +		dev_err(dev, "device name %s not recognized.\n", lsm9ds0->name);
> +		return -ENODEV;
> +	}
> +
> +	lsm9ds0->magn = devm_iio_device_alloc(dev, sizeof(*data));
> +	if (!lsm9ds0->magn)
> +		return -ENOMEM;
> +
> +	lsm9ds0->magn->name = lsm9ds0->name;
> +
> +	data = iio_priv(lsm9ds0->magn);
> +	data->sensor_settings = (struct st_sensor_settings *)settings;
> +	data->dev = dev;
> +	data->irq = lsm9ds0->irq;
> +	data->regmap = regmap;
> +	data->vdd = lsm9ds0->vdd;
> +	data->vdd_io = lsm9ds0->vdd_io;
> +
> +	return st_magn_common_probe(lsm9ds0->magn);
> +}
> +
> +int st_lsm9ds0_probe(struct st_lsm9ds0 *lsm9ds0, struct regmap *regmap)
> +{
> +	int ret;
> +
> +	ret = devm_st_lsm9ds0_power_enable(lsm9ds0);
> +	if (ret)
> +		return ret;
> +
> +	/* Setup accelerometer device */
> +	ret = st_lsm9ds0_probe_accel(lsm9ds0, regmap);
> +	if (ret)
> +		return ret;
> +
> +	/* Setup magnetometer device */
> +	ret = st_lsm9ds0_probe_magn(lsm9ds0, regmap);
> +	if (ret)
> +		st_accel_common_remove(lsm9ds0->accel);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(st_lsm9ds0_probe);
> +
> +int st_lsm9ds0_remove(struct st_lsm9ds0 *lsm9ds0)
> +{
> +	st_magn_common_remove(lsm9ds0->magn);
> +	st_accel_common_remove(lsm9ds0->accel);
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(st_lsm9ds0_remove);
> +
> +MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
> +MODULE_DESCRIPTION("STMicroelectronics LSM9DS0 IMU core driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_i2c.c b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_i2c.c
> new file mode 100644
> index 000000000000..50a36ab53bc3
> --- /dev/null
> +++ b/drivers/iio/imu/st_lsm9ds0/st_lsm9ds0_i2c.c
> @@ -0,0 +1,84 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * STMicroelectronics LSM9DS0 IMU driver
> + *
> + * Copyright (C) 2021, Intel Corporation
> + *
> + * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> + */
> +
> +#include <linux/i2c.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +
> +#include <linux/iio/common/st_sensors_i2c.h>
> +
> +#include "st_lsm9ds0.h"
> +
> +static const struct of_device_id st_lsm9ds0_of_match[] = {
> +	{
> +		.compatible = "st,lsm9ds0-imu",
> +		.data = LSM9DS0_IMU_DEV_NAME,
> +	},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, st_lsm9ds0_of_match);
> +
> +static const struct i2c_device_id st_lsm9ds0_id_table[] = {
> +	{ LSM9DS0_IMU_DEV_NAME },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, st_lsm9ds0_id_table);
> +
> +static const struct regmap_config st_lsm9ds0_regmap_config = {
> +	.reg_bits	= 8,
> +	.val_bits	= 8,
> +	.read_flag_mask	= 0x80,
> +};
> +
> +static int st_lsm9ds0_i2c_probe(struct i2c_client *client)
> +{
> +	const struct regmap_config *config = &st_lsm9ds0_regmap_config;
> +	struct device *dev = &client->dev;
> +	struct st_lsm9ds0 *lsm9ds0;
> +	struct regmap *regmap;
> +
> +	st_sensors_dev_name_probe(dev, client->name, sizeof(client->name));
> +
> +	lsm9ds0 = devm_kzalloc(dev, sizeof(*lsm9ds0), GFP_KERNEL);
> +	if (!lsm9ds0)
> +		return -ENOMEM;
> +
> +	lsm9ds0->dev = dev;
> +	lsm9ds0->name = client->name;
> +	lsm9ds0->irq = client->irq;
> +
> +	regmap = devm_regmap_init_i2c(client, config);
> +	if (IS_ERR(regmap))
> +		return PTR_ERR(regmap);
> +
> +	i2c_set_clientdata(client, lsm9ds0);
> +
> +	return st_lsm9ds0_probe(lsm9ds0, regmap);
> +}
> +
> +static int st_lsm9ds0_i2c_remove(struct i2c_client *client)
> +{
> +	return st_lsm9ds0_remove(i2c_get_clientdata(client));
> +}
> +
> +static struct i2c_driver st_lsm9ds0_driver = {
> +	.driver = {
> +		.name = "st-lsm9ds0-i2c",
> +		.of_match_table = st_lsm9ds0_of_match,
> +	},
> +	.probe_new = st_lsm9ds0_i2c_probe,
> +	.remove = st_lsm9ds0_i2c_remove,
> +	.id_table = st_lsm9ds0_id_table,
> +};
> +module_i2c_driver(st_lsm9ds0_driver);
> +
> +MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
> +MODULE_DESCRIPTION("STMicroelectronics LSM9DS0 IMU I2C driver");
> +MODULE_LICENSE("GPL v2");

Re: [PATCH v1 6/7] iio: st_sensors: Add lsm9ds0 IMU support

[Andy Shevchenko]

On Sun, Apr 18, 2021 at 2:07 PM Jonathan Cameron <jic23@kernel.org> wrote:

Thanks for review, my answers below.

> On Wed, 14 Apr 2021 22:54:53 +0300
> Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
>
> > We can utilize separate drivers for accelerometer and magnetometer,
> > so here is the glue driver to enable LSM9DS0 IMU support.
> >
> > The idea was suggested by Crestez Dan Leonard in [1]. The proposed change
> > was sent as RFC due to race condition concerns, which are indeed possible.
>
> If you are going to mention races, good to give some flavour in here!

I meant that the initial idea is racy due to different devices
communicating to the same i2c address.
So, any sequence of transfers are not serialized and you may end up with

drv1 -> i2c
drv2 -> i2c
drv1 <- i2c # garbage

> This driver makes me very nervous indeed.

Why?! This one is race free as far as I can see. Or maybe I interpret
this wrongly and you are talking about initial RFC?

>  I haven't 'found' any places
> where the fact we'll write the same registers from each of the drivers
> causes problems (e.g. int pin setup etc) but perhaps I'm missing something.
>
> Shall we say that makes me rather keener to get eyes (and thought) on this
> patch than normal :)

How should I amend the commit message to state:
1. First idea (RFC by the link) *is* racy AFAIU
2. This one *is not* racy.

> > In order to amend the initial change,

You see, *in order to amend*, so here is the *amended* version.

> I went further by providing a specific
> > multi-instantiate probe driver that reuses existing accelerometer and
> > magnetometer.
> >
> > [1]: https://lore.kernel.org/patchwork/patch/670353/
> >
> > Suggested-by: Crestez Dan Leonard <leonard.crestez@intel.com>
> > Cc: mr.lahorde@laposte.net
> > Cc: Matija Podravec <matija_podravec@fastmail.fm>
> > Cc: Sergey Borishchenko <borischenko.sergey@gmail.com>
> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>
> A few comments in here, though mostly about stuff related to the origin code
> you are copying so perhaps not tidying them up is preferable because it would
> complicate comparison of the two cases.

...

> > +     {
> > +             .wai = 0x49,
> > +             .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
> > +             .sensors_supported = {
> > +                     [0] = LSM9DS0_IMU_DEV_NAME,
>
> What does the name attribute report for these?
>
> Previously we've had the _accel etc postfix to differentiate the devices. I don't
> suppose it matters to much though as easy enough to identify the accelerometer
> etc from what channels are present.
>
> Of course driver may get name from somewhere different anyway, I haven't checked,
> just noticed this was different and wondered what the affect might be.

Yes, it has a postfix, that's why I leave it like this.

...

> > +static int st_lsm9ds0_power_enable(struct device *dev, struct st_lsm9ds0 *lsm9ds0)
> > +{
> > +     int ret;
> > +
> > +     /* Regulators not mandatory, but if requested we should enable them. */
>
> That's a bit of a missleading comment though cut and paste from the other driver
> code.  Key is that they will be handled by stub regulators if we don't provide
> the which is not really what that comment implies.

I see. I will remove it.

> > +     lsm9ds0->vdd = devm_regulator_get(dev, "vdd");
> > +     if (IS_ERR(lsm9ds0->vdd)) {
> > +             dev_err(dev, "unable to get Vdd supply\n");
> > +             return PTR_ERR(lsm9ds0->vdd);
> > +     }
> > +     ret = regulator_enable(lsm9ds0->vdd);
> > +     if (ret) {
> > +             dev_warn(dev, "Failed to enable specified Vdd supply\n");
>
> Given we fail to probe if this is true, dev_warn seems a bit soft.

Right.  I'll move to dev_err().

> > +             return ret;
> > +     }
> > +
> > +     lsm9ds0->vdd_io = devm_regulator_get(dev, "vddio");
> > +     if (IS_ERR(lsm9ds0->vdd_io)) {
> > +             dev_err(dev, "unable to get Vdd_IO supply\n");
> > +             regulator_disable(lsm9ds0->vdd);
> > +             return PTR_ERR(lsm9ds0->vdd_io);
> > +     }
> > +     ret = regulator_enable(lsm9ds0->vdd_io);
> > +     if (ret) {
> > +             dev_warn(dev, "Failed to enable specified Vdd_IO supply\n");

Ditto.

> > +             regulator_disable(lsm9ds0->vdd);
> > +             return ret;
> > +     }
> > +
> > +     return 0;
> > +}

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v1 6/7] iio: st_sensors: Add lsm9ds0 IMU support

[Andy Shevchenko]

On Sun, Apr 18, 2021 at 4:49 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Sun, Apr 18, 2021 at 2:07 PM Jonathan Cameron <jic23@kernel.org> wrote:
>
> Thanks for review, my answers below.
>
> > On Wed, 14 Apr 2021 22:54:53 +0300
> > Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> >
> > > We can utilize separate drivers for accelerometer and magnetometer,
> > > so here is the glue driver to enable LSM9DS0 IMU support.
> > >
> > > The idea was suggested by Crestez Dan Leonard in [1]. The proposed change
> > > was sent as RFC due to race condition concerns, which are indeed possible.
> >
> > If you are going to mention races, good to give some flavour in here!
>
> I meant that the initial idea is racy due to different devices
> communicating to the same i2c address.
> So, any sequence of transfers are not serialized and you may end up with
>
> drv1 -> i2c
> drv2 -> i2c
> drv1 <- i2c # garbage
>
> > This driver makes me very nervous indeed.
>
> Why?! This one is race free as far as I can see. Or maybe I interpret
> this wrongly and you are talking about initial RFC?
>
> >  I haven't 'found' any places
> > where the fact we'll write the same registers from each of the drivers
> > causes problems (e.g. int pin setup etc) but perhaps I'm missing something.
> >
> > Shall we say that makes me rather keener to get eyes (and thought) on this
> > patch than normal :)
>
> How should I amend the commit message to state:
> 1. First idea (RFC by the link) *is* racy AFAIU
> 2. This one *is not* racy.

I re-read this and now understand better what you meant.
So, it may be that the initial proposal may work without any
amendment, but since I haven't investigated much, I should rather use
the phrase "potentially racy". In my variant it's using one regmap for
both drivers (not two), which makes the register state consistent. Am
I wrong?
Do we have some places where we may write to the same register concurrently?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v1 6/7] iio: st_sensors: Add lsm9ds0 IMU support

[Jonathan Cameron]

On Sun, 18 Apr 2021 16:59:02 +0300
Andy Shevchenko <andy.shevchenko@gmail.com> wrote:

> On Sun, Apr 18, 2021 at 4:49 PM Andy Shevchenko
> <andy.shevchenko@gmail.com> wrote:
> >
> > On Sun, Apr 18, 2021 at 2:07 PM Jonathan Cameron <jic23@kernel.org> wrote:
> >
> > Thanks for review, my answers below.
> >  
> > > On Wed, 14 Apr 2021 22:54:53 +0300
> > > Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> > >  
> > > > We can utilize separate drivers for accelerometer and magnetometer,
> > > > so here is the glue driver to enable LSM9DS0 IMU support.
> > > >
> > > > The idea was suggested by Crestez Dan Leonard in [1]. The proposed change
> > > > was sent as RFC due to race condition concerns, which are indeed possible.  
> > >
> > > If you are going to mention races, good to give some flavour in here!  
> >
> > I meant that the initial idea is racy due to different devices
> > communicating to the same i2c address.
> > So, any sequence of transfers are not serialized and you may end up with
> >
> > drv1 -> i2c
> > drv2 -> i2c
> > drv1 <- i2c # garbage
> >  
> > > This driver makes me very nervous indeed.  
> >
> > Why?! This one is race free as far as I can see. Or maybe I interpret
> > this wrongly and you are talking about initial RFC?
> >  
> > >  I haven't 'found' any places
> > > where the fact we'll write the same registers from each of the drivers
> > > causes problems (e.g. int pin setup etc) but perhaps I'm missing something.
> > >
> > > Shall we say that makes me rather keener to get eyes (and thought) on this
> > > patch than normal :)  
> >
> > How should I amend the commit message to state:
> > 1. First idea (RFC by the link) *is* racy AFAIU
> > 2. This one *is not* racy.  

Great.  I read it as meaning they were both potentially racey!
This is less worrying.

> 
> I re-read this and now understand better what you meant.
> So, it may be that the initial proposal may work without any
> amendment, but since I haven't investigated much, I should rather use
> the phrase "potentially racy". In my variant it's using one regmap for
> both drivers (not two), which makes the register state consistent. Am
> I wrong?

I think this approach is fine.  I'd be more worried about the two 'sub' drivers
not necessarily being happy that someone else touches state they care about.
There are places where I think we write the same value to the same register
twice during setup with this model, but that shouldn't matter.   I'm not 100%
sure that there aren't other cases though I think there aren't.

So what you have is probably fine, but more eyes would make me happier ;)

Lots of people care about this particular driver so hopefully we'll get
them.

> Do we have some places where we may write to the same register concurrently?
> 
Only ones I can find are the setup ones where it writes the same value twice
I think.  So *crosses fingers* :)

Given timing (missed merge window) we have masses of time to let this sit
on list a while and see if anyone can spot issues neither of us have found.

Jonathan

[PATCH v1 7/7] dt-bindings: iio: st,st-sensors: Add LSM9DS0 compatible string

[Andy Shevchenko]

Enumerate LSM9DS0 (accelerometer and magnetometer parts) via
'st,lsm9ds0-imu' compatible string.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 Documentation/devicetree/bindings/iio/st,st-sensors.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/iio/st,st-sensors.yaml b/Documentation/devicetree/bindings/iio/st,st-sensors.yaml
index db291a9390b7..43d29a7d46f1 100644
--- a/Documentation/devicetree/bindings/iio/st,st-sensors.yaml
+++ b/Documentation/devicetree/bindings/iio/st,st-sensors.yaml
@@ -74,6 +74,8 @@ properties:
       - st,lps33hw
       - st,lps35hw
       - st,lps22hh
+        # IMU
+      - st,lsm9ds0-imu
 
   reg:
     maxItems: 1
-- 
2.30.2

Re: [PATCH v1 7/7] dt-bindings: iio: st,st-sensors: Add LSM9DS0 compatible string

[Rob Herring]

On Wed, 14 Apr 2021 22:54:54 +0300, Andy Shevchenko wrote:
> Enumerate LSM9DS0 (accelerometer and magnetometer parts) via
> 'st,lsm9ds0-imu' compatible string.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  Documentation/devicetree/bindings/iio/st,st-sensors.yaml | 2 ++
>  1 file changed, 2 insertions(+)
> 

Acked-by: Rob Herring <robh@kernel.org>

Re: [PATCH v1 7/7] dt-bindings: iio: st,st-sensors: Add LSM9DS0 compatible string

[Jonathan Cameron]

On Wed, 14 Apr 2021 22:54:54 +0300
Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:

> Enumerate LSM9DS0 (accelerometer and magnetometer parts) via
> 'st,lsm9ds0-imu' compatible string.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
This one crossed with a cleanup set from Linus so I've adjusted it to match
the new style of that file.

Series applied to togreg branch of iio.git and pushed out as testing for
the autobuilders to see if we missed anything.

Thanks,

Jonathan

> ---
>  Documentation/devicetree/bindings/iio/st,st-sensors.yaml | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/iio/st,st-sensors.yaml b/Documentation/devicetree/bindings/iio/st,st-sensors.yaml
> index db291a9390b7..43d29a7d46f1 100644
> --- a/Documentation/devicetree/bindings/iio/st,st-sensors.yaml
> +++ b/Documentation/devicetree/bindings/iio/st,st-sensors.yaml
> @@ -74,6 +74,8 @@ properties:
>        - st,lps33hw
>        - st,lps35hw
>        - st,lps22hh
> +        # IMU
> +      - st,lsm9ds0-imu
>  
>    reg:
>      maxItems: 1